mcs/class/corlib/System/Type.cs

   1 //
   2 // System.Type.cs
   3 //
   4 // Author:
   5 //   Miguel de Icaza (miguel@ximian.com)
   6 //
   7 // (C) Ximian, Inc.  http://www.ximian.com
   8 //
   9
  10 //
  11 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System.Diagnostics;
  34 using System.Reflection;
  35 using System.Reflection.Emit;
  36 using System.Collections;
  37 using System.Runtime.InteropServices;
  38 using System.Runtime.CompilerServices;
  39 using System.Globalization;
  40
  41 namespace System {
  42
  43         [Serializable]
  44         [ClassInterface (ClassInterfaceType.None)]
  45         [ComVisible (true)]
  46         [ComDefaultInterface (typeof (_Type))]
  47         public abstract class Type : MemberInfo, IReflect, _Type {
  48
  49                 internal RuntimeTypeHandle _impl;
  50
  51                 public static readonly char Delimiter = '.';
  52                 public static readonly Type[] EmptyTypes = {};
  53                 public static readonly MemberFilter FilterAttribute = new MemberFilter (FilterAttribute_impl);
  54                 public static readonly MemberFilter FilterName = new MemberFilter (FilterName_impl);
  55                 public static readonly MemberFilter FilterNameIgnoreCase = new MemberFilter (FilterNameIgnoreCase_impl);
  56                 public static readonly object Missing = System.Reflection.Missing.Value;
  57
  58                 internal const BindingFlags DefaultBindingFlags =
  59                 BindingFlags.Public | BindingFlags.Static | BindingFlags.Instance;
  60
  61                 /* implementation of the delegates for MemberFilter */
  62                 static bool FilterName_impl (MemberInfo m, object filterCriteria)
  63                 {
  64                         string name = (string) filterCriteria;
  65                         if (name == null || name.Length == 0 )
  66                                 return false; // because m.Name cannot be null or empty
  67
  68                         if (name [name.Length-1] == '*')
  69                                 return string.CompareOrdinal (name, 0, m.Name, 0, name.Length-1) == 0;
  70
  71                 return name.Equals (m.Name);
  72                 }
  73
  74                 static bool FilterNameIgnoreCase_impl (MemberInfo m, object filterCriteria)
  75                 {
  76                         string name = (string) filterCriteria;
  77                         if (name == null || name.Length == 0 )
  78                                 return false; // because m.Name cannot be null or empty
  79
  80                         if (name [name.Length-1] == '*')
  81                                 return string.Compare (name, 0, m.Name, 0, name.Length-1, StringComparison.OrdinalIgnoreCase) == 0;
  82
  83                         return string.Equals (name, m.Name, StringComparison.OrdinalIgnoreCase);
  84                 }
  85
  86                 static bool FilterAttribute_impl (MemberInfo m, object filterCriteria)
  87                 {
  88                         int flags = ((IConvertible)filterCriteria).ToInt32 (null);
  89                         if (m is MethodInfo)
  90                                 return ((int)((MethodInfo)m).Attributes & flags) != 0;
  91                         if (m is FieldInfo)
  92                                 return ((int)((FieldInfo)m).Attributes & flags) != 0;
  93                         if (m is PropertyInfo)
  94                                 return ((int)((PropertyInfo)m).Attributes & flags) != 0;
  95                         if (m is EventInfo)
  96                                 return ((int)((EventInfo)m).Attributes & flags) != 0;
  97                         return false;
  98                 }
  99
 100                 protected Type ()
 101                 {
 102                 }
 103
 104                 /// <summary>
 105                 ///   The assembly where the type is defined.
 106                 /// </summary>
 107                 public abstract Assembly Assembly {
 108                         get;
 109                 }
 110
 111                 /// <summary>
 112                 ///   Gets the fully qualified name for the type including the
 113                 ///   assembly name where the type is defined.
 114                 /// </summary>
 115                 public abstract string AssemblyQualifiedName {
 116                         get;
 117                 }
 118
 119                 /// <summary>
 120                 ///   Returns the Attributes associated with the type.
 121                 /// </summary>
 122                 public TypeAttributes Attributes {
 123                         get {
 124                                 return GetAttributeFlagsImpl ();
 125                         }
 126                 }
 127
 128                 /// <summary>
 129                 ///   Returns the basetype for this type
 130                 /// </summary>
 131                 public abstract Type BaseType {
 132                         get;
 133                 }
 134
 135                 /// <summary>
 136                 ///   Returns the class that declares the member.
 137                 /// </summary>
 138                 public override Type DeclaringType {
 139                         get {
 140                                 return null;
 141                         }
 142                 }
 143
 144                 /// <summary>
 145                 ///
 146                 /// </summary>
 147                 public static Binder DefaultBinder {
 148                         get {
 149                                 return Binder.DefaultBinder;
 150                         }
 151                 }
 152
 153                 /// <summary>
 154                 ///    The full name of the type including its namespace
 155                 /// </summary>
 156                 public abstract string FullName {
 157                         get;
 158                 }
 159
 160                 public abstract Guid GUID {
 161                         get;
 162                 }
 163
 164                 public bool HasElementType {
 165                         get {
 166                                 return HasElementTypeImpl ();
 167                         }
 168                 }
 169
 170                 public bool IsAbstract {
 171                         get {
 172                                 return (Attributes & TypeAttributes.Abstract) != 0;
 173                         }
 174                 }
 175
 176                 public bool IsAnsiClass {
 177                         get {
 178                                 return (Attributes & TypeAttributes.StringFormatMask)
 179                                 == TypeAttributes.AnsiClass;
 180                         }
 181                 }
 182
 183                 public bool IsArray {
 184                         get {
 185                                 return IsArrayImpl ();
 186                         }
 187                 }
 188
 189                 public bool IsAutoClass {
 190                         get {
 191                                 return (Attributes & TypeAttributes.StringFormatMask) == TypeAttributes.AutoClass;
 192                         }
 193                 }
 194
 195                 public bool IsAutoLayout {
 196                         get {
 197                                 return (Attributes & TypeAttributes.LayoutMask) == TypeAttributes.AutoLayout;
 198                         }
 199                 }
 200
 201                 public bool IsByRef {
 202                         get {
 203                                 return IsByRefImpl ();
 204                         }
 205                 }
 206
 207                 public bool IsClass {
 208                         get {
 209                                 if (IsInterface)
 210                                         return false;
 211
 212                                 return !IsValueType;
 213                         }
 214                 }
 215
 216                 public bool IsCOMObject {
 217                         get {
 218                                 return IsCOMObjectImpl ();
 219                         }
 220                 }
 221
 222                 public bool IsContextful {
 223                         get {
 224                                 return IsContextfulImpl ();
 225                         }
 226                 }
 227
 228                 public
 229 #if NET_4_0
 230                 virtual
 231 #endif
 232                 bool IsEnum {
 233                         get {
 234                                 return IsSubclassOf (typeof (Enum));
 235                         }
 236                 }
 237
 238                 public bool IsExplicitLayout {
 239                         get {
 240                                 return (Attributes & TypeAttributes.LayoutMask) == TypeAttributes.ExplicitLayout;
 241                         }
 242                 }
 243
 244                 public bool IsImport {
 245                         get {
 246                                 return (Attributes & TypeAttributes.Import) != 0;
 247                         }
 248                 }
 249
 250                 public bool IsInterface {
 251                         get {
 252                                 return (Attributes & TypeAttributes.ClassSemanticsMask) == TypeAttributes.Interface;
 253                         }
 254                 }
 255
 256                 public bool IsLayoutSequential {
 257                         get {
 258                                 return (Attributes & TypeAttributes.LayoutMask) == TypeAttributes.SequentialLayout;
 259                         }
 260                 }
 261
 262                 public bool IsMarshalByRef {
 263                         get {
 264                                 return IsMarshalByRefImpl ();
 265                         }
 266                 }
 267
 268                 public bool IsNestedAssembly {
 269                         get {
 270                                 return (Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.NestedAssembly;
 271                         }
 272                 }
 273
 274                 public bool IsNestedFamANDAssem {
 275                         get {
 276                                 return (Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.NestedFamANDAssem;
 277                         }
 278                 }
 279
 280                 public bool IsNestedFamily {
 281                         get {
 282                                 return (Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.NestedFamily;
 283                         }
 284                 }
 285
 286                 public bool IsNestedFamORAssem {
 287                         get {
 288                                 return (Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.NestedFamORAssem;
 289                         }
 290                 }
 291
 292                 public bool IsNestedPrivate {
 293                         get {
 294                                 return (Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.NestedPrivate;
 295                         }
 296                 }
 297
 298                 public bool IsNestedPublic {
 299                         get {
 300                                 return (Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.NestedPublic;
 301                         }
 302                 }
 303
 304                 public bool IsNotPublic {
 305                         get {
 306                                 return (Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.NotPublic;
 307                         }
 308                 }
 309
 310                 public bool IsPointer {
 311                         get {
 312                                 return IsPointerImpl ();
 313                         }
 314                 }
 315
 316                 public bool IsPrimitive {
 317                         get {
 318                                 return IsPrimitiveImpl ();
 319                         }
 320                 }
 321
 322                 public bool IsPublic {
 323                         get {
 324                                 return (Attributes & TypeAttributes.VisibilityMask) == TypeAttributes.Public;
 325                         }
 326                 }
 327
 328                 public bool IsSealed {
 329                         get {
 330                                 return (Attributes & TypeAttributes.Sealed) != 0;
 331                         }
 332                 }
 333
 334                 public
 335 #if NET_4_0
 336                 virtual
 337 #endif
 338                 bool IsSerializable {
 339                         get {
 340                                 if ((Attributes & TypeAttributes.Serializable) != 0)
 341                                         return true;
 342
 343                                 // Enums and delegates are always serializable
 344
 345                                 Type type = UnderlyingSystemType;
 346                                 if (type == null)
 347                                         return false;
 348
 349                                 // Fast check for system types
 350                                 if (type.IsSystemType)
 351                                         return type_is_subtype_of (type, typeof (Enum), false) || type_is_subtype_of (type, typeof (Delegate), false);
 352
 353                                 // User defined types depend on this behavior
 354                                 do {
 355                                         if ((type == typeof (Enum)) || (type == typeof (Delegate)))
 356                                                 return true;
 357
 358                                         type = type.BaseType;
 359                                 } while (type != null);
 360
 361                                 return false;
 362                         }
 363                 }
 364
 365                 public bool IsSpecialName {
 366                         get {
 367                                 return (Attributes & TypeAttributes.SpecialName) != 0;
 368                         }
 369                 }
 370
 371                 public bool IsUnicodeClass {
 372                         get {
 373                                 return (Attributes & TypeAttributes.StringFormatMask) == TypeAttributes.UnicodeClass;
 374                         }
 375                 }
 376
 377                 public bool IsValueType {
 378                         get {
 379                                 return IsValueTypeImpl ();
 380                         }
 381                 }
 382
 383                 public override MemberTypes MemberType {
 384                         get {return MemberTypes.TypeInfo;}
 385                 }
 386
 387                 override
 388                 public abstract Module Module {get;}
 389
 390                 public abstract string Namespace {get;}
 391
 392                 public override Type ReflectedType {
 393                         get {
 394                                 return null;
 395                         }
 396                 }
 397
 398                 public virtual RuntimeTypeHandle TypeHandle {
 399                         get { throw new ArgumentException ("Derived class must provide implementation."); }
 400                 }
 401
 402                 [ComVisible (true)]
 403                 public ConstructorInfo TypeInitializer {
 404                         get {
 405                                 return GetConstructorImpl (
 406                                         BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Static,
 407                                         null,
 408                                         CallingConventions.Any,
 409                                         EmptyTypes,
 410                                         null);
 411                         }
 412                 }
 413
 414                 /*
 415                  * This has NOTHING to do with getting the base type of an enum. Use
 416                  * Enum.GetUnderlyingType () for that.
 417                  */
 418                 public abstract Type UnderlyingSystemType {get;}
 419
 420                 public override bool Equals (object o)
 421                 {
 422 #if NET_4_0
 423                         return Equals (o as Type);
 424 #else
 425                         if (o == this)
 426                                 return true;
 427
 428                         Type me = UnderlyingSystemType;
 429                         if (me == null)
 430                                 return false;
 431                         return me.EqualsInternal (o as Type);
 432 #endif
 433                 }
 434
 435 #if NET_4_0
 436                 public virtual bool Equals (Type o)
 437                 {
 438 #else
 439                 public bool Equals (Type o)
 440                 {
 441
 442                         if (o == this)
 443                                 return true;
 444 #endif
 445                         if (o == null)
 446                                 return false;
 447                         Type me = UnderlyingSystemType;
 448                         if (me == null)
 449                                 return false;
 450                         return me.EqualsInternal (o.UnderlyingSystemType);
 451                 }
 452
 453 #if NET_4_0
 454                 [MonoTODO ("Implement it properly once 4.0 impl details are known.")]
 455                 public static bool operator == (Type left, Type right)
 456                 {
 457                         return Object.ReferenceEquals (left, right);
 458                 }
 459
 460                 [MonoTODO ("Implement it properly once 4.0 impl details are known.")]
 461                 public static bool operator != (Type left, Type right)
 462                 {
 463                         return !Object.ReferenceEquals (left, right);
 464                 }
 465
 466                 [MonoInternalNote ("Reimplement this in MonoType for bonus speed")]
 467                 public virtual Type GetEnumUnderlyingType () {
 468                         if (!IsEnum)
 469                                 throw new ArgumentException ("Type is not an enumeration", "enumType");
 470
 471                         var fields = GetFields (BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);
 472
 473                         if (fields == null || fields.Length != 1)
 474                                 throw new ArgumentException ("An enum must have exactly one instance field", "enumType");
 475
 476                         return fields [0].FieldType;
 477                 }
 478
 479                 [MonoInternalNote ("Reimplement this in MonoType for bonus speed")]
 480                 public virtual string[] GetEnumNames () {
 481                         if (!IsEnum)
 482                                 throw new ArgumentException ("Type is not an enumeration", "enumType");
 483
 484                         var fields = GetFields (BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Static);
 485
 486                         string [] result = new string [fields.Length];
 487                         for (int i = 0; i < fields.Length; ++i)
 488                                 result [i] = fields [i].Name;
 489
 490                         return result;
 491                 }
 492
 493                 NotImplementedException CreateNIE () {
 494                         return new NotImplementedException ();
 495                 }
 496
 497                 public virtual Array GetEnumValues () {
 498                         if (!IsEnum)
 499                                 throw new ArgumentException ("Type is not an enumeration", "enumType");
 500
 501                         throw CreateNIE ();
 502                 }
 503
 504                 bool IsValidEnumType (Type type) {
 505                         return (type.IsPrimitive && type != typeof (bool) && type != typeof (double) && type != typeof (float)) || type.IsEnum;
 506                 }
 507
 508                 [MonoInternalNote ("Reimplement this in MonoType for bonus speed")]
 509                 public virtual string GetEnumName (object value) {
 510                         if (value == null)
 511                                 throw new ArgumentException ("Value is null", "value");
 512                         if (!IsValidEnumType (value.GetType ()))
 513                                 throw new ArgumentException ("Value is not the enum or a valid enum underlying type", "value");
 514                         if (!IsEnum)
 515                                 throw new ArgumentException ("Type is not an enumeration", "enumType");
 516
 517                         object obj = null;
 518                         var fields = GetFields (BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Static);
 519
 520                         for (int i = 0; i < fields.Length; ++i) {
 521                                 var fv = fields [i].GetValue (null);
 522                                 if (obj == null) {
 523                                         try {
 524                                                 //XXX we can't use 'this' as argument as it might be an UserType
 525                                                 obj = Enum.ToObject (fv.GetType (), value);
 526                                         } catch (OverflowException) {
 527                                                 return null;
 528                                         } catch (InvalidCastException) {
 529                                                 throw new ArgumentException ("Value is not valid", "value");
 530                                         }
 531                                 }
 532                                 if (fv.Equals (obj))
 533                                         return fields [i].Name;
 534                         }
 535
 536                         return null;
 537                 }
 538
 539                 [MonoInternalNote ("Reimplement this in MonoType for bonus speed")]
 540                 public virtual bool IsEnumDefined (object value) {
 541                         if (value == null)
 542                                 throw new ArgumentException ("Value is null", "value");
 543                         if (!IsEnum)
 544                                 throw new ArgumentException ("Type is not an enumeration", "enumType");
 545
 546                         Type vt = value.GetType ();
 547                         if (!IsValidEnumType (vt) && vt != typeof (string))
 548                                 throw new InvalidOperationException ("Value is not the enum or a valid enum underlying type");
 549
 550                         var fields = GetFields (BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Static);
 551
 552                         if (value is string) {
 553                                 for (int i = 0; i < fields.Length; ++i) {
 554                                         if (fields [i].Name.Equals (value))
 555                                                 return true;
 556                                 }
 557                         } else {
 558                                 if (vt != this && vt != GetEnumUnderlyingType ())
 559                                         throw new ArgumentException ("Value is not the enum or a valid enum underlying type", "value");
 560
 561                                 object obj = null;
 562                                 for (int i = 0; i < fields.Length; ++i) {
 563                                         var fv = fields [i].GetValue (null);
 564                                         if (obj == null) {
 565                                                 try {
 566                                                         //XXX we can't use 'this' as argument as it might be an UserType
 567                                                         obj = Enum.ToObject (fv.GetType (), value);
 568                                                 } catch (OverflowException) {
 569                                                         return false;
 570                                                 } catch (InvalidCastException) {
 571                                                         throw new ArgumentException ("Value is not valid", "value");
 572                                                 }
 573                                         }
 574                                         if (fv.Equals (obj))
 575                                                 return true;
 576                                 }
 577                         }
 578                         return false;
 579                 }
 580
 581                 public static Type GetType (string typeName, Func<AssemblyName,Assembly> assemblyResolver, Func<Assembly,string,bool,Type> typeResolver)
 582                 {
 583                         return GetType (typeName, assemblyResolver, typeResolver, false, false);
 584                 }
 585
 586                 public static Type GetType (string typeName, Func<AssemblyName,Assembly> assemblyResolver, Func<Assembly,string,bool,Type> typeResolver, bool throwOnError)
 587                 {
 588                         return GetType (typeName, assemblyResolver, typeResolver, throwOnError, false);
 589                 }
 590
 591                 public static Type GetType (string typeName, Func<AssemblyName,Assembly> assemblyResolver, Func<Assembly,string,bool,Type> typeResolver, bool throwOnError, bool ignoreCase)
 592                 {
 593                         TypeSpec spec = TypeSpec.Parse (typeName);
 594                         return spec.Resolve (assemblyResolver, typeResolver, throwOnError, ignoreCase);
 595                 }
 596
 597 #endif
 598
 599                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 600                 internal extern bool EqualsInternal (Type type);
 601
 602                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 603                 private static extern Type internal_from_handle (IntPtr handle);
 604
 605                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 606                 private static extern Type internal_from_name (string name, bool throwOnError, bool ignoreCase);
 607
 608                 public static Type GetType(string typeName)
 609                 {
 610                         if (typeName == null)
 611                                 throw new ArgumentNullException ("TypeName");
 612
 613                         return internal_from_name (typeName, false, false);
 614                 }
 615
 616                 public static Type GetType(string typeName, bool throwOnError)
 617                 {
 618                         if (typeName == null)
 619                                 throw new ArgumentNullException ("TypeName");
 620
 621                         Type type = internal_from_name (typeName, throwOnError, false);
 622                         if (throwOnError && type == null)
 623                                 throw new TypeLoadException ("Error loading '" + typeName + "'");
 624
 625                         return type;
 626                 }
 627
 628                 public static Type GetType(string typeName, bool throwOnError, bool ignoreCase)
 629                 {
 630                         if (typeName == null)
 631                                 throw new ArgumentNullException ("TypeName");
 632
 633                         Type t = internal_from_name (typeName, throwOnError, ignoreCase);
 634                         if (throwOnError && t == null)
 635                                 throw new TypeLoadException ("Error loading '" + typeName + "'");
 636
 637                         return t;
 638                 }
 639
 640                 public static Type[] GetTypeArray (object[] args) {
 641                         if (args == null)
 642                                 throw new ArgumentNullException ("args");
 643
 644                         Type[] ret;
 645                         ret = new Type [args.Length];
 646                         for (int i = 0; i < args.Length; ++i)
 647                                 ret [i] = args[i].GetType ();
 648                         return ret;
 649                 }
 650
 651                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 652                 internal extern static TypeCode GetTypeCodeInternal (Type type);
 653
 654 #if NET_4_0
 655                 protected virtual
 656 #endif
 657                 TypeCode GetTypeCodeImpl () {
 658                         Type type = this;
 659                         if (type is MonoType)
 660                                 return GetTypeCodeInternal (type);
 661
 662                         type = type.UnderlyingSystemType;
 663
 664                         if (!type.IsSystemType)
 665                                 return TypeCode.Object;
 666                         else
 667                                 return GetTypeCodeInternal (type);
 668                 }
 669
 670                 public static TypeCode GetTypeCode (Type type) {
 671                         if (type == null)
 672                                 /* MS.NET returns this */
 673                                 return TypeCode.Empty;
 674                         return type.GetTypeCodeImpl ();
 675                 }
 676
 677                 [MonoTODO("This operation is currently not supported by Mono")]
 678                 public static Type GetTypeFromCLSID (Guid clsid)
 679                 {
 680                         throw new NotImplementedException ();
 681                 }
 682
 683                 [MonoTODO("This operation is currently not supported by Mono")]
 684                 public static Type GetTypeFromCLSID (Guid clsid, bool throwOnError)
 685                 {
 686                         throw new NotImplementedException ();
 687                 }
 688
 689                 [MonoTODO("This operation is currently not supported by Mono")]
 690                 public static Type GetTypeFromCLSID (Guid clsid, string server)
 691                 {
 692                         throw new NotImplementedException ();
 693                 }
 694
 695                 [MonoTODO("This operation is currently not supported by Mono")]
 696                 public static Type GetTypeFromCLSID (Guid clsid, string server, bool throwOnError)
 697                 {
 698                         throw new NotImplementedException ();
 699                 }
 700
 701                 public static Type GetTypeFromHandle (RuntimeTypeHandle handle)
 702                 {
 703                         if (handle.Value == IntPtr.Zero)
 704                                 // This is not consistent with the other GetXXXFromHandle methods, but
 705                                 // MS.NET seems to do this
 706                                 return null;
 707
 708                         return internal_from_handle (handle.Value);
 709                 }
 710
 711                 [MonoTODO("Mono does not support COM")]
 712                 public static Type GetTypeFromProgID (string progID)
 713                 {
 714                         throw new NotImplementedException ();
 715                 }
 716
 717                 [MonoTODO("Mono does not support COM")]
 718                 public static Type GetTypeFromProgID (string progID, bool throwOnError)
 719                 {
 720                         throw new NotImplementedException ();
 721                 }
 722
 723                 [MonoTODO("Mono does not support COM")]
 724                 public static Type GetTypeFromProgID (string progID, string server)
 725                 {
 726                         throw new NotImplementedException ();
 727                 }
 728
 729                 [MonoTODO("Mono does not support COM")]
 730                 public static Type GetTypeFromProgID (string progID, string server, bool throwOnError)
 731                 {
 732                         throw new NotImplementedException ();
 733                 }
 734
 735                 public static RuntimeTypeHandle GetTypeHandle (object o)
 736                 {
 737                         if (o == null)
 738                                 throw new ArgumentNullException ();
 739
 740                         return o.GetType().TypeHandle;
 741                 }
 742
 743                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 744                 internal static extern bool type_is_subtype_of (Type a, Type b, bool check_interfaces);
 745
 746                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 747                 internal static extern bool type_is_assignable_from (Type a, Type b);
 748
 749                 public new Type GetType ()
 750                 {
 751                         return base.GetType ();
 752                 }
 753
 754                 [ComVisible (true)]
 755                 public virtual bool IsSubclassOf (Type c)
 756                 {
 757                         if (c == null || c == this)
 758                                 return false;
 759
 760                         // Fast check for system types
 761                         if (IsSystemType)
 762                                 return c.IsSystemType && type_is_subtype_of (this, c, false);
 763
 764                         // User defined types depend on this behavior
 765                         for (Type type = BaseType; type != null; type = type.BaseType)
 766                                 if (type == c)
 767                                         return true;
 768
 769                         return false;
 770                 }
 771
 772                 public virtual Type[] FindInterfaces (TypeFilter filter, object filterCriteria)
 773                 {
 774                         if (filter == null)
 775                                 throw new ArgumentNullException ("filter");
 776
 777                         ArrayList ifaces = new ArrayList ();
 778                         foreach (Type iface in GetInterfaces ()) {
 779                                 if (filter (iface, filterCriteria))
 780                                         ifaces.Add (iface);
 781                         }
 782
 783                         return (Type []) ifaces.ToArray (typeof (Type));
 784                 }
 785
 786                 public Type GetInterface (string name) {
 787                         return GetInterface (name, false);
 788                 }
 789
 790                 public abstract Type GetInterface (string name, bool ignoreCase);
 791
 792                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 793                 internal static extern void GetInterfaceMapData (Type t, Type iface, out MethodInfo[] targets, out MethodInfo[] methods);
 794
 795                 [ComVisible (true)]
 796                 public virtual InterfaceMapping GetInterfaceMap (Type interfaceType) {
 797                         if (!IsSystemType)
 798                                 throw new NotSupportedException ("Derived classes must provide an implementation.");
 799                         if (!interfaceType.IsSystemType)
 800                                 throw new ArgumentException ("interfaceType", "Type is an user type");
 801                         InterfaceMapping res;
 802                         if (interfaceType == null)
 803                                 throw new ArgumentNullException ("interfaceType");
 804                         if (!interfaceType.IsInterface)
 805                                 throw new ArgumentException (Locale.GetText ("Argument must be an interface."), "interfaceType");
 806                         if (IsInterface)
 807                                 throw new ArgumentException ("'this' type cannot be an interface itself");
 808                         res.TargetType = this;
 809                         res.InterfaceType = interfaceType;
 810                         GetInterfaceMapData (this, interfaceType, out res.TargetMethods, out res.InterfaceMethods);
 811                         if (res.TargetMethods == null)
 812                                 throw new ArgumentException (Locale.GetText ("Interface not found"), "interfaceType");
 813
 814                         return res;
 815                 }
 816
 817                 public abstract Type[] GetInterfaces ();
 818
 819                 public virtual bool IsAssignableFrom (Type c)
 820                 {
 821                         if (c == null)
 822                                 return false;
 823
 824                         if (Equals (c))
 825                                 return true;
 826
 827                         if (c is TypeBuilder)
 828                                 return ((TypeBuilder)c).IsAssignableTo (this);
 829
 830                         /* Handle user defined type classes */
 831                         if (!IsSystemType) {
 832                                 Type systemType = UnderlyingSystemType;
 833                                 if (!systemType.IsSystemType)
 834                                         return false;
 835
 836                                 Type other = c.UnderlyingSystemType;
 837                                 if (!other.IsSystemType)
 838                                         return false;
 839
 840                                 return systemType.IsAssignableFrom (other);
 841                         }
 842
 843                         if (!c.IsSystemType) {
 844                                 Type underlyingType = c.UnderlyingSystemType;
 845                                 if (!underlyingType.IsSystemType)
 846                                         return false;
 847                                 return IsAssignableFrom (underlyingType);
 848                         }
 849
 850                         return type_is_assignable_from (this, c);
 851                 }
 852
 853                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 854                 extern static bool IsInstanceOfType (Type type, object o);
 855
 856                 public virtual bool IsInstanceOfType (object o)
 857                 {
 858                         Type type = UnderlyingSystemType;
 859                         if (!type.IsSystemType)
 860                                 return false;
 861                         return IsInstanceOfType (type, o);
 862                 }
 863
 864                 public virtual int GetArrayRank ()
 865                 {
 866                         throw new NotSupportedException ();     // according to MSDN
 867                 }
 868
 869                 public abstract Type GetElementType ();
 870
 871                 public EventInfo GetEvent (string name)
 872                 {
 873                         return GetEvent (name, DefaultBindingFlags);
 874                 }
 875
 876                 public abstract EventInfo GetEvent (string name, BindingFlags bindingAttr);
 877
 878                 public virtual EventInfo[] GetEvents ()
 879                 {
 880                         return GetEvents (DefaultBindingFlags);
 881                 }
 882
 883                 public abstract EventInfo[] GetEvents (BindingFlags bindingAttr);
 884
 885                 public FieldInfo GetField( string name)
 886                 {
 887                         return GetField (name, DefaultBindingFlags);
 888                 }
 889
 890                 public abstract FieldInfo GetField( string name, BindingFlags bindingAttr);
 891
 892                 public FieldInfo[] GetFields ()
 893                 {
 894                         return GetFields (DefaultBindingFlags);
 895                 }
 896
 897                 public abstract FieldInfo[] GetFields (BindingFlags bindingAttr);
 898
 899                 public override int GetHashCode()
 900                 {
 901                         Type t = UnderlyingSystemType;
 902                         if (t != null && t != this)
 903                                 return t.GetHashCode ();
 904                         return (int)_impl.Value;
 905                 }
 906
 907                 public MemberInfo[] GetMember (string name)
 908                 {
 909                         return GetMember (name, MemberTypes.All, DefaultBindingFlags);
 910                 }
 911
 912                 public virtual MemberInfo[] GetMember (string name, BindingFlags bindingAttr)
 913                 {
 914                         return GetMember (name, MemberTypes.All, bindingAttr);
 915                 }
 916
 917                 public virtual MemberInfo[] GetMember (string name, MemberTypes type, BindingFlags bindingAttr)
 918                 {
 919                         if (name == null)
 920                                 throw new ArgumentNullException ("name");
 921                         if ((bindingAttr & BindingFlags.IgnoreCase) != 0)
 922                                 return FindMembers (type, bindingAttr, FilterNameIgnoreCase, name);
 923                         else
 924                                 return FindMembers (type, bindingAttr, FilterName, name);
 925                 }
 926
 927                 public MemberInfo[] GetMembers ()
 928                 {
 929                         return GetMembers (DefaultBindingFlags);
 930                 }
 931
 932                 public abstract MemberInfo[] GetMembers (BindingFlags bindingAttr);
 933
 934                 public MethodInfo GetMethod (string name)
 935                 {
 936                         if (name == null)
 937                                 throw new ArgumentNullException ("name");
 938                         return GetMethodImpl (name, DefaultBindingFlags, null, CallingConventions.Any, null, null);
 939                 }
 940
 941                 public MethodInfo GetMethod (string name, BindingFlags bindingAttr)
 942                 {
 943                         if (name == null)
 944                                 throw new ArgumentNullException ("name");
 945
 946                         return GetMethodImpl (name, bindingAttr, null, CallingConventions.Any, null, null);
 947                 }
 948
 949                 public MethodInfo GetMethod (string name, Type[] types)
 950                 {
 951                         return GetMethod (name, DefaultBindingFlags, null, CallingConventions.Any, types, null);
 952                 }
 953
 954                 public MethodInfo GetMethod (string name, Type[] types, ParameterModifier[] modifiers)
 955                 {
 956                         return GetMethod (name, DefaultBindingFlags, null, CallingConventions.Any, types, modifiers);
 957                 }
 958
 959                 public MethodInfo GetMethod (string name, BindingFlags bindingAttr, Binder binder,
 960                                              Type[] types, ParameterModifier[] modifiers)
 961                 {
 962                         return GetMethod (name, bindingAttr, binder, CallingConventions.Any, types, modifiers);
 963                 }
 964
 965                 public MethodInfo GetMethod (string name, BindingFlags bindingAttr, Binder binder,
 966                                              CallingConventions callConvention, Type[] types, ParameterModifier[] modifiers)
 967                 {
 968                         if (name == null)
 969                                 throw new ArgumentNullException ("name");
 970                         if (types == null)
 971                                 throw new ArgumentNullException ("types");
 972
 973                         for (int i = 0; i < types.Length; i++)
 974                                 if (types[i] == null)
 975                                         throw new ArgumentNullException ("types");
 976
 977                         return GetMethodImpl (name, bindingAttr, binder, callConvention, types, modifiers);
 978                 }
 979
 980                 protected abstract MethodInfo GetMethodImpl (string name, BindingFlags bindingAttr, Binder binder,
 981                                                              CallingConventions callConvention, Type[] types,
 982                                                              ParameterModifier[] modifiers);
 983
 984                 internal MethodInfo GetMethodImplInternal (string name, BindingFlags bindingAttr, Binder binder,
 985                                                                                                                         CallingConventions callConvention, Type[] types,
 986                                                                                                                         ParameterModifier[] modifiers)
 987                 {
 988                         return GetMethodImpl (name, bindingAttr, binder, callConvention, types, modifiers);
 989                 }
 990
 991                 internal virtual MethodInfo GetMethod (MethodInfo fromNoninstanciated)
 992                 {
 993                         throw new System.InvalidOperationException ("can only be called in generic type");
 994                 }
 995
 996                 internal virtual ConstructorInfo GetConstructor (ConstructorInfo fromNoninstanciated)
 997                 {
 998                         throw new System.InvalidOperationException ("can only be called in generic type");
 999                 }
1000
1001                 internal virtual FieldInfo GetField (FieldInfo fromNoninstanciated)
1002                 {
1003                         throw new System.InvalidOperationException ("can only be called in generic type");
1004                 }
1005
1006
1007                 public MethodInfo[] GetMethods ()
1008                 {
1009                         return GetMethods (DefaultBindingFlags);
1010                 }
1011
1012                 public abstract MethodInfo[] GetMethods (BindingFlags bindingAttr);
1013
1014                 public Type GetNestedType (string name)
1015                 {
1016                         return GetNestedType (name, DefaultBindingFlags);
1017                 }
1018
1019                 public abstract Type GetNestedType (string name, BindingFlags bindingAttr);
1020
1021                 public Type[] GetNestedTypes ()
1022                 {
1023                         return GetNestedTypes (DefaultBindingFlags);
1024                 }
1025
1026                 public abstract Type[] GetNestedTypes (BindingFlags bindingAttr);
1027
1028
1029                 public PropertyInfo[] GetProperties ()
1030                 {
1031                         return GetProperties (DefaultBindingFlags);
1032                 }
1033
1034                 public abstract PropertyInfo[] GetProperties (BindingFlags bindingAttr);
1035
1036
1037                 public PropertyInfo GetProperty (string name)
1038                 {
1039                         if (name == null)
1040                                 throw new ArgumentNullException ("name");
1041
1042                         return GetPropertyImpl (name, DefaultBindingFlags, null, null, null, null);
1043                 }
1044
1045                 public PropertyInfo GetProperty (string name, BindingFlags bindingAttr)
1046                 {
1047                         if (name == null)
1048                                 throw new ArgumentNullException ("name");
1049                         return GetPropertyImpl (name, bindingAttr, null, null, null, null);
1050                 }
1051
1052                 public PropertyInfo GetProperty (string name, Type returnType)
1053                 {
1054                         if (name == null)
1055                                 throw new ArgumentNullException ("name");
1056                         return GetPropertyImpl (name, DefaultBindingFlags, null, returnType, null, null);
1057                 }
1058
1059                 public PropertyInfo GetProperty (string name, Type[] types)
1060                 {
1061                         return GetProperty (name, DefaultBindingFlags, null, null, types, null);
1062                 }
1063
1064                 public PropertyInfo GetProperty (string name, Type returnType, Type[] types)
1065                 {
1066                         return GetProperty (name, DefaultBindingFlags, null, returnType, types, null);
1067                 }
1068
1069                 public PropertyInfo GetProperty( string name, Type returnType, Type[] types, ParameterModifier[] modifiers)
1070                 {
1071                         return GetProperty (name, DefaultBindingFlags, null, returnType, types, modifiers);
1072                 }
1073
1074                 public PropertyInfo GetProperty (string name, BindingFlags bindingAttr, Binder binder, Type returnType,
1075                                                  Type[] types, ParameterModifier[] modifiers)
1076                 {
1077                         if (name == null)
1078                                 throw new ArgumentNullException ("name");
1079                         if (types == null)
1080                                 throw new ArgumentNullException ("types");
1081
1082                         foreach (Type t in types) {
1083                                 if (t == null)
1084                                         throw new ArgumentNullException ("types");
1085                         }
1086
1087                         return GetPropertyImpl (name, bindingAttr, binder, returnType, types, modifiers);
1088                 }
1089
1090                 protected abstract PropertyInfo GetPropertyImpl (string name, BindingFlags bindingAttr, Binder binder,
1091                                                                  Type returnType, Type[] types, ParameterModifier[] modifiers);
1092
1093                 internal PropertyInfo GetPropertyImplInternal (string name, BindingFlags bindingAttr, Binder binder,
1094                                                                                                            Type returnType, Type[] types, ParameterModifier[] modifiers)
1095                 {
1096                         return GetPropertyImpl (name, bindingAttr, binder, returnType, types, modifiers);
1097                 }
1098
1099                 protected abstract ConstructorInfo GetConstructorImpl (BindingFlags bindingAttr,
1100                                                                        Binder binder,
1101                                                                        CallingConventions callConvention,
1102                                                                        Type[] types,
1103                                                                        ParameterModifier[] modifiers);
1104
1105                 protected abstract TypeAttributes GetAttributeFlagsImpl ();
1106                 protected abstract bool HasElementTypeImpl ();
1107                 protected abstract bool IsArrayImpl ();
1108                 protected abstract bool IsByRefImpl ();
1109                 protected abstract bool IsCOMObjectImpl ();
1110                 protected abstract bool IsPointerImpl ();
1111                 protected abstract bool IsPrimitiveImpl ();
1112
1113                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1114                 internal static extern bool IsArrayImpl (Type type);
1115
1116                 protected virtual bool IsValueTypeImpl ()
1117                 {
1118                         if (this == typeof (ValueType) || this == typeof (Enum))
1119                                 return false;
1120
1121                         return IsSubclassOf (typeof (ValueType));
1122                 }
1123
1124                 protected virtual bool IsContextfulImpl ()
1125                 {
1126                         return typeof (ContextBoundObject).IsAssignableFrom (this);
1127                 }
1128
1129                 protected virtual bool IsMarshalByRefImpl ()
1130                 {
1131                         return typeof (MarshalByRefObject).IsAssignableFrom (this);
1132                 }
1133
1134                 [ComVisible (true)]
1135                 public ConstructorInfo GetConstructor (Type[] types)
1136                 {
1137                         return GetConstructor (BindingFlags.Public|BindingFlags.Instance, null, CallingConventions.Any, types, null);
1138                 }
1139
1140                 [ComVisible (true)]
1141                 public ConstructorInfo GetConstructor (BindingFlags bindingAttr, Binder binder,
1142                                                        Type[] types, ParameterModifier[] modifiers)
1143                 {
1144                         return GetConstructor (bindingAttr, binder, CallingConventions.Any, types, modifiers);
1145                 }
1146
1147                 [ComVisible (true)]
1148                 public ConstructorInfo GetConstructor (BindingFlags bindingAttr, Binder binder,
1149                                                        CallingConventions callConvention,
1150                                                        Type[] types, ParameterModifier[] modifiers)
1151                 {
1152                         if (types == null)
1153                                 throw new ArgumentNullException ("types");
1154
1155                         foreach (Type t in types) {
1156                                 if (t == null)
1157                                         throw new ArgumentNullException ("types");
1158                         }
1159
1160                         return GetConstructorImpl (bindingAttr, binder, callConvention, types, modifiers);
1161                 }
1162
1163                 [ComVisible (true)]
1164                 public ConstructorInfo[] GetConstructors ()
1165                 {
1166                         return GetConstructors (BindingFlags.Public | BindingFlags.Instance);
1167                 }
1168
1169                 [ComVisible (true)]
1170                 public abstract ConstructorInfo[] GetConstructors (BindingFlags bindingAttr);
1171
1172                 public virtual MemberInfo[] GetDefaultMembers ()
1173                 {
1174                         object [] att = GetCustomAttributes (typeof (DefaultMemberAttribute), true);
1175                         if (att.Length == 0)
1176                                 return new MemberInfo [0];
1177
1178                         MemberInfo [] member = GetMember (((DefaultMemberAttribute) att [0]).MemberName);
1179                         return (member != null) ? member : new MemberInfo [0];
1180                 }
1181
1182                 public virtual MemberInfo[] FindMembers (MemberTypes memberType, BindingFlags bindingAttr,
1183                                                          MemberFilter filter, object filterCriteria)
1184                 {
1185                         MemberInfo[] result;
1186                         ArrayList l = new ArrayList ();
1187
1188                         // Console.WriteLine ("FindMembers for {0} (Type: {1}): {2}",
1189                         // this.FullName, this.GetType().FullName, this.obj_address());
1190                         if ((memberType & MemberTypes.Method) != 0) {
1191                                 MethodInfo[] c = GetMethods (bindingAttr);
1192                                 if (filter != null) {
1193                                         foreach (MemberInfo m in c) {
1194                                                 if (filter (m, filterCriteria))
1195                                                         l.Add (m);
1196                                         }
1197                                 } else {
1198                                         l.AddRange (c);
1199                                 }
1200                         }
1201                         if ((memberType & MemberTypes.Constructor) != 0) {
1202                                 ConstructorInfo[] c = GetConstructors (bindingAttr);
1203                                 if (filter != null) {
1204                                         foreach (MemberInfo m in c) {
1205                                                 if (filter (m, filterCriteria))
1206                                                         l.Add (m);
1207                                         }
1208                                 } else {
1209                                         l.AddRange (c);
1210                                 }
1211                         }
1212                         if ((memberType & MemberTypes.Property) != 0) {
1213                                 PropertyInfo[] c;
1214                                 int count = l.Count;
1215                                 Type ptype;
1216                                 if (filter != null) {
1217                                         ptype = this;
1218                                         while ((l.Count == count) && (ptype != null)) {
1219                                                 c = ptype.GetProperties (bindingAttr);
1220                                                 foreach (MemberInfo m in c) {
1221                                                         if (filter (m, filterCriteria))
1222                                                                 l.Add (m);
1223                                                 }
1224                                                 ptype = ptype.BaseType;
1225                                         }
1226                                 } else {
1227                                         c = GetProperties (bindingAttr);
1228                                         l.AddRange (c);
1229                                 }
1230                         }
1231                         if ((memberType & MemberTypes.Event) != 0) {
1232                                 EventInfo[] c = GetEvents (bindingAttr);
1233                                 if (filter != null) {
1234                                         foreach (MemberInfo m in c) {
1235                                                 if (filter (m, filterCriteria))
1236                                                         l.Add (m);
1237                                         }
1238                                 } else {
1239                                         l.AddRange (c);
1240                                 }
1241                         }
1242                         if ((memberType & MemberTypes.Field) != 0) {
1243                                 FieldInfo[] c = GetFields (bindingAttr);
1244                                 if (filter != null) {
1245                                         foreach (MemberInfo m in c) {
1246                                                 if (filter (m, filterCriteria))
1247                                                         l.Add (m);
1248                                         }
1249                                 } else {
1250                                         l.AddRange (c);
1251                                 }
1252                         }
1253                         if ((memberType & MemberTypes.NestedType) != 0) {
1254                                 Type[] c = GetNestedTypes (bindingAttr);
1255                                 if (filter != null) {
1256                                         foreach (MemberInfo m in c) {
1257                                                 if (filter (m, filterCriteria)) {
1258                                                         l.Add (m);
1259                                                 }
1260                                         }
1261                                 } else {
1262                                         l.AddRange (c);
1263                                 }
1264                         }
1265
1266                         switch (memberType) {
1267                         case MemberTypes.Constructor :
1268                                 result = new ConstructorInfo [l.Count];
1269                                 break;
1270                         case MemberTypes.Event :
1271                                 result = new EventInfo [l.Count];
1272                                 break;
1273                         case MemberTypes.Field :
1274                                 result = new FieldInfo [l.Count];
1275                                 break;
1276                         case MemberTypes.Method :
1277                                 result = new MethodInfo [l.Count];
1278                                 break;
1279                         case MemberTypes.NestedType :
1280                         case MemberTypes.TypeInfo :
1281                                 result = new Type [l.Count];
1282                                 break;
1283                         case MemberTypes.Property :
1284                                 result = new PropertyInfo [l.Count];
1285                                 break;
1286                         default :
1287                                 result = new MemberInfo [l.Count];
1288                                 break;
1289                         }
1290                         l.CopyTo (result);
1291                         return result;
1292                 }
1293
1294                 [DebuggerHidden]
1295                 [DebuggerStepThrough]
1296                 public object InvokeMember (string name, BindingFlags invokeAttr, Binder binder, object target, object[] args)
1297                 {
1298                         return InvokeMember (name, invokeAttr, binder, target, args, null, null, null);
1299                 }
1300
1301                 [DebuggerHidden]
1302                 [DebuggerStepThrough]
1303                 public object InvokeMember (string name, BindingFlags invokeAttr, Binder binder,
1304                                             object target, object[] args, CultureInfo culture)
1305                 {
1306                         return InvokeMember (name, invokeAttr, binder, target, args, null, culture, null);
1307                 }
1308
1309                 public abstract object InvokeMember (string name, BindingFlags invokeAttr,
1310                                                      Binder binder, object target, object[] args,
1311                                                      ParameterModifier[] modifiers,
1312                                                      CultureInfo culture, string[] namedParameters);
1313
1314                 public override string ToString()
1315                 {
1316                         return FullName;
1317                 }
1318
1319                 internal virtual bool IsCompilerContext {
1320                         get {
1321                                 AssemblyBuilder builder = Assembly as AssemblyBuilder;
1322                                 return builder != null && builder.IsCompilerContext;
1323                         }
1324                 }
1325
1326                 internal bool IsSystemType {
1327                         get {
1328                                 return _impl.Value != IntPtr.Zero;
1329                         }
1330                 }
1331
1332                 public virtual Type[] GetGenericArguments ()
1333                 {
1334                         throw new NotSupportedException ();
1335                 }
1336
1337                 public virtual bool ContainsGenericParameters {
1338                         get { return false; }
1339                 }
1340
1341                 public virtual extern bool IsGenericTypeDefinition {
1342                         [MethodImplAttribute(MethodImplOptions.InternalCall)]
1343                         get;
1344                 }
1345
1346                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1347                 internal extern Type GetGenericTypeDefinition_impl ();
1348
1349                 public virtual Type GetGenericTypeDefinition ()
1350                 {
1351                         throw new NotSupportedException ("Derived classes must provide an implementation.");
1352                 }
1353
1354                 public virtual extern bool IsGenericType {
1355                         [MethodImplAttribute(MethodImplOptions.InternalCall)]
1356                         get;
1357                 }
1358
1359                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1360                 static extern Type MakeGenericType (Type gt, Type [] types);
1361
1362                 static AssemblyBuilder PeelAssemblyBuilder (Type type)
1363                 {
1364                         if (type.Assembly is AssemblyBuilder)
1365                                 return (AssemblyBuilder)type.Assembly;
1366
1367                         if (type.HasElementType)
1368                                 return PeelAssemblyBuilder (type.GetElementType ());
1369
1370                         if (!type.IsGenericType || type.IsGenericParameter || type.IsGenericTypeDefinition)
1371                                 return null;
1372
1373                         foreach (Type arg in type.GetGenericArguments ()) {
1374                                 AssemblyBuilder ab = PeelAssemblyBuilder (arg);
1375                                 if (ab != null)
1376                                         return ab;
1377                         }
1378                         return null;
1379                 }
1380
1381                 public virtual Type MakeGenericType (params Type[] typeArguments)
1382                 {
1383                         if (IsUserType)
1384                                 throw new NotSupportedException ();
1385                         if (!IsGenericTypeDefinition)
1386                                 throw new InvalidOperationException ("not a generic type definition");
1387                         if (typeArguments == null)
1388                                 throw new ArgumentNullException ("typeArguments");
1389                         if (GetGenericArguments().Length != typeArguments.Length)
1390                                 throw new ArgumentException (String.Format ("The type or method has {0} generic parameter(s) but {1} generic argument(s) where provided. A generic argument must be provided for each generic parameter.", GetGenericArguments ().Length, typeArguments.Length), "typeArguments");
1391
1392                         bool hasUserType = false;
1393                         AssemblyBuilder compilerContext = null;
1394
1395                         Type[] systemTypes = new Type[typeArguments.Length];
1396                         for (int i = 0; i < typeArguments.Length; ++i) {
1397                                 Type t = typeArguments [i];
1398                                 if (t == null)
1399                                         throw new ArgumentNullException ("typeArguments");
1400
1401                                 if (!(t is MonoType))
1402                                         hasUserType = true;
1403                                 if (t.IsCompilerContext)
1404                                         compilerContext = PeelAssemblyBuilder (t);
1405                                 systemTypes [i] = t;
1406                         }
1407
1408                         if (hasUserType) {
1409                                 if (compilerContext != null)
1410                                         return compilerContext.MakeGenericType (this, typeArguments);
1411                                 return new MonoGenericClass (this, typeArguments);
1412                         }
1413
1414                         Type res = MakeGenericType (this, systemTypes);
1415                         if (res == null)
1416                                 throw new TypeLoadException ();
1417                         return res;
1418                 }
1419
1420                 public virtual bool IsGenericParameter {
1421                         get {
1422                                 return false;
1423                         }
1424                 }
1425
1426                 public bool IsNested {
1427                         get {
1428                                 return DeclaringType != null;
1429                         }
1430                 }
1431
1432                 public bool IsVisible {
1433                         get {
1434                                 if (IsNestedPublic)
1435                                         return DeclaringType.IsVisible;
1436
1437                                 return IsPublic;
1438                         }
1439                 }
1440
1441                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1442                 extern int GetGenericParameterPosition ();
1443
1444                 public virtual int GenericParameterPosition {
1445                         get {
1446                                 int res = GetGenericParameterPosition ();
1447                                 if (res < 0)
1448                                         throw new InvalidOperationException ();
1449                                 return res;
1450                         }
1451                 }
1452
1453                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1454                 extern GenericParameterAttributes GetGenericParameterAttributes ();
1455
1456                 public virtual GenericParameterAttributes GenericParameterAttributes {
1457                         get {
1458                                 if (!IsSystemType)
1459                                         throw new NotSupportedException ("Derived classes must provide an implementation.");
1460
1461                                 if (!IsGenericParameter)
1462                                         throw new InvalidOperationException ();
1463
1464                                 return GetGenericParameterAttributes ();
1465                         }
1466                 }
1467
1468                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1469                 extern Type[] GetGenericParameterConstraints_impl ();
1470
1471                 public virtual Type[] GetGenericParameterConstraints ()
1472                 {
1473                         if (!IsSystemType)
1474                                 throw new InvalidOperationException ();
1475
1476                         if (!IsGenericParameter)
1477                                 throw new InvalidOperationException ();
1478
1479                         return GetGenericParameterConstraints_impl ();
1480                 }
1481
1482                 public virtual MethodBase DeclaringMethod {
1483                         get {
1484                                 return null;
1485                         }
1486                 }
1487
1488                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1489                 extern Type make_array_type (int rank);
1490
1491                 public virtual Type MakeArrayType ()
1492                 {
1493                         if (!IsSystemType)
1494                                 throw new NotSupportedException ("Derived classes must provide an implementation.");
1495                         return make_array_type (0);
1496                 }
1497
1498                 public virtual Type MakeArrayType (int rank)
1499                 {
1500                         if (!IsSystemType)
1501                                 throw new NotSupportedException ("Derived classes must provide an implementation.");
1502                         if (rank < 1 || rank > 255)
1503                                 throw new IndexOutOfRangeException ();
1504                         return make_array_type (rank);
1505                 }
1506
1507                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1508                 extern Type make_byref_type ();
1509
1510                 public virtual Type MakeByRefType ()
1511                 {
1512                         if (!IsSystemType)
1513                                 throw new NotSupportedException ("Derived classes must provide an implementation.");
1514                         if (IsByRef)
1515                                 throw new TypeLoadException ("Can not call MakeByRefType on a ByRef type");
1516                         return make_byref_type ();
1517                 }
1518
1519                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1520                 static extern Type MakePointerType (Type type);
1521
1522                 public virtual Type MakePointerType ()
1523                 {
1524                         if (!IsSystemType)
1525                                 throw new NotSupportedException ("Derived classes must provide an implementation.");
1526                         return MakePointerType (this);
1527                 }
1528
1529                 public static Type ReflectionOnlyGetType (string typeName,
1530                                                           bool throwIfNotFound,
1531                                                           bool ignoreCase)
1532                 {
1533                         if (typeName == null)
1534                                 throw new ArgumentNullException ("typeName");
1535                         int idx = typeName.IndexOf (',');
1536                         if (idx < 0 || idx == 0 || idx == typeName.Length - 1)
1537                                 throw new ArgumentException ("Assembly qualifed type name is required", "typeName");
1538                         string an = typeName.Substring (idx + 1);
1539                         Assembly a;
1540                         try {
1541                                 a = Assembly.ReflectionOnlyLoad (an);
1542                         } catch {
1543                                 if (throwIfNotFound)
1544                                         throw;
1545                                 return null;
1546                         }
1547                         return a.GetType (typeName.Substring (0, idx), throwIfNotFound, ignoreCase);
1548                 }
1549
1550                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
1551                 extern void GetPacking (out int packing, out int size);
1552
1553                 public virtual StructLayoutAttribute StructLayoutAttribute {
1554                         get {
1555                                 LayoutKind kind;
1556
1557                                 if (IsLayoutSequential)
1558                                         kind = LayoutKind.Sequential;
1559                                 else if (IsExplicitLayout)
1560                                         kind = LayoutKind.Explicit;
1561                                 else
1562                                         kind = LayoutKind.Auto;
1563
1564                                 StructLayoutAttribute attr = new StructLayoutAttribute (kind);
1565
1566                                 if (IsUnicodeClass)
1567                                         attr.CharSet = CharSet.Unicode;
1568                                 else if (IsAnsiClass)
1569                                         attr.CharSet = CharSet.Ansi;
1570                                 else
1571                                         attr.CharSet = CharSet.Auto;
1572
1573                                 if (kind != LayoutKind.Auto)
1574                                         GetPacking (out attr.Pack, out attr.Size);
1575
1576                                 return attr;
1577                         }
1578                 }
1579
1580                 internal object[] GetPseudoCustomAttributes ()
1581                 {
1582                         int count = 0;
1583
1584                         /* IsSerializable returns true for delegates/enums as well */
1585                         if ((Attributes & TypeAttributes.Serializable) != 0)
1586                                 count ++;
1587                         if ((Attributes & TypeAttributes.Import) != 0)
1588                                 count ++;
1589
1590                         if (count == 0)
1591                                 return null;
1592                         object[] attrs = new object [count];
1593                         count = 0;
1594
1595                         if ((Attributes & TypeAttributes.Serializable) != 0)
1596                                 attrs [count ++] = new SerializableAttribute ();
1597                         if ((Attributes & TypeAttributes.Import) != 0)
1598                                 attrs [count ++] = new ComImportAttribute ();
1599
1600                         return attrs;
1601                 }
1602
1603
1604 #if NET_4_0 || BOOTSTRAP_NET_4_0
1605                 public virtual bool IsEquivalentTo (Type other)
1606                 {
1607                         return this == other;
1608                 }
1609 #endif
1610
1611                 /*
1612                  * Return whenever this object is an instance of a user defined subclass
1613                  * of System.Type or an instance of TypeDelegator.
1614                  */
1615                 internal bool IsUserType {
1616                         get {
1617                                 /*
1618                                  * subclasses cannot modify _impl so if it is zero, it means the
1619                                  * type is not created by the runtime.
1620                                  */
1621                                 return _impl.Value == IntPtr.Zero &&
1622                                         (GetType ().Assembly != typeof (Type).Assembly || GetType () == typeof (TypeDelegator));
1623                         }
1624                 }
1625
1626                 void _Type.GetIDsOfNames ([In] ref Guid riid, IntPtr rgszNames, uint cNames, uint lcid, IntPtr rgDispId)
1627                 {
1628                         throw new NotImplementedException ();
1629                 }
1630
1631                 void _Type.GetTypeInfo (uint iTInfo, uint lcid, IntPtr ppTInfo)
1632                 {
1633                         throw new NotImplementedException ();
1634                 }
1635
1636                 void _Type.GetTypeInfoCount (out uint pcTInfo)
1637                 {
1638                         throw new NotImplementedException ();
1639                 }
1640
1641                 void _Type.Invoke (uint dispIdMember, [In] ref Guid riid, uint lcid, short wFlags, IntPtr pDispParams, IntPtr pVarResult, IntPtr pExcepInfo, IntPtr puArgErr)
1642                 {
1643                         throw new NotImplementedException ();
1644                 }
1645         }
1646 }