mcs/class/System.Configuration/System.Configuration/ConfigurationElementCollection.cs

   1 //
   2 // System.Configuration.ConfigurationElementCollection.cs
   3 //
   4 // Authors:
   5 //      Tim Coleman (tim@timcoleman.com)
   6 //
   7 // Copyright (C) Tim Coleman, 2004
   8
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  30 //
  31
  32 #if NET_2_0
  33
  34 using System.Collections;
  35 using System.Diagnostics;
  36 using System.Xml;
  37
  38 namespace System.Configuration
  39 {
  40         [DebuggerDisplayAttribute ("Count = {Count}")]
  41         public abstract partial class ConfigurationElementCollection : ConfigurationElement, ICollection, IEnumerable
  42         {
  43                 ArrayList list = new ArrayList ();
  44                 ArrayList removed;
  45                 ArrayList inherited;
  46                 bool emitClear;
  47                 bool modified;
  48                 IComparer comparer;
  49                 int inheritedLimitIndex;
  50
  51                 string addElementName = "add";
  52                 string clearElementName = "clear";
  53                 string removeElementName = "remove";
  54
  55                 #region Constructors
  56
  57                 protected ConfigurationElementCollection ()
  58                 {
  59                 }
  60
  61                 protected ConfigurationElementCollection (IComparer comparer)
  62                 {
  63                         this.comparer = comparer;
  64                 }
  65
  66                 internal override void InitFromProperty (PropertyInformation propertyInfo)
  67                 {
  68                         ConfigurationCollectionAttribute colat = propertyInfo.Property.CollectionAttribute;
  69
  70                         if (colat == null)
  71                                 colat = Attribute.GetCustomAttribute (propertyInfo.Type, typeof (ConfigurationCollectionAttribute)) as ConfigurationCollectionAttribute;
  72
  73                         if (colat != null) {
  74                                 addElementName = colat.AddItemName;
  75                                 clearElementName = colat.ClearItemsName;
  76                                 removeElementName = colat.RemoveItemName;
  77                         }
  78                         base.InitFromProperty (propertyInfo);
  79                 }
  80
  81                 #endregion // Constructors
  82
  83                 #region Properties
  84
  85                 public virtual ConfigurationElementCollectionType CollectionType {
  86                         get { return ConfigurationElementCollectionType.AddRemoveClearMap; }
  87                 }
  88
  89                 bool IsBasic {
  90                         get {
  91                                 return CollectionType == ConfigurationElementCollectionType.BasicMap ||
  92                                                 CollectionType == ConfigurationElementCollectionType.BasicMapAlternate;
  93                         }
  94                 }
  95
  96                 bool IsAlternate {
  97                         get {
  98                                 return CollectionType == ConfigurationElementCollectionType.AddRemoveClearMapAlternate ||
  99                                                 CollectionType == ConfigurationElementCollectionType.BasicMapAlternate;
 100                         }
 101                 }
 102
 103                 public int Count {
 104                         get { return list.Count; }
 105                 }
 106
 107                 protected virtual string ElementName {
 108                         get { return string.Empty; }
 109                 }
 110
 111                 public bool EmitClear {
 112                         get { return emitClear; }
 113                         set { emitClear = value; }
 114                 }
 115
 116                 public bool IsSynchronized {
 117                         get { return false; }
 118                 }
 119
 120                 public object SyncRoot {
 121                         get { return this; }
 122                 }
 123
 124                 protected virtual bool ThrowOnDuplicate {
 125                         get {
 126                                 if (CollectionType != ConfigurationElementCollectionType.AddRemoveClearMap &&
 127                                     CollectionType != ConfigurationElementCollectionType.AddRemoveClearMapAlternate)
 128                                         return false;
 129
 130                                 return true;
 131                         }
 132                 }
 133
 134                 protected internal string AddElementName {
 135                         get { return addElementName; }
 136                         set { addElementName = value; }
 137                 }
 138
 139                 protected internal string ClearElementName {
 140                         get { return clearElementName; }
 141                         set { clearElementName = value; }
 142                 }
 143
 144                 protected internal string RemoveElementName {
 145                         get { return removeElementName; }
 146                         set { removeElementName = value; }
 147                 }
 148
 149                 #endregion // Properties
 150
 151                 #region Methods
 152
 153                 protected virtual void BaseAdd (ConfigurationElement element)
 154                 {
 155                         BaseAdd (element, ThrowOnDuplicate);
 156                 }
 157
 158                 protected void BaseAdd (ConfigurationElement element, bool throwIfExists)
 159                 {
 160                         if (IsReadOnly ())
 161                                 throw new ConfigurationErrorsException ("Collection is read only.");
 162
 163                         if (IsAlternate) {
 164                                 list.Insert (inheritedLimitIndex, element);
 165                                 inheritedLimitIndex++;
 166                         }
 167                         else {
 168                                 int old_index = IndexOfKey (GetElementKey (element));
 169                                 if (old_index >= 0) {
 170                                         if (element.Equals (list [old_index]))
 171                                                 return;
 172                                         if (throwIfExists)
 173                                                 throw new ConfigurationException ("Duplicate element in collection");
 174                                         list.RemoveAt (old_index);
 175                                 }
 176                                 list.Add (element);
 177                         }
 178
 179                         modified = true;
 180                 }
 181
 182                 protected virtual void BaseAdd (int index, ConfigurationElement element)
 183                 {
 184                         if (ThrowOnDuplicate && BaseIndexOf (element) != -1)
 185                                 throw new ConfigurationException ("Duplicate element in collection");
 186                         if (IsReadOnly ())
 187                                 throw new ConfigurationErrorsException ("Collection is read only.");
 188
 189                         if (IsAlternate && (index > inheritedLimitIndex))
 190                                 throw new ConfigurationErrorsException ("Can't insert new elements below the inherited elements.");
 191                         if (!IsAlternate && (index <= inheritedLimitIndex))
 192                                 throw new ConfigurationErrorsException ("Can't insert new elements above the inherited elements.");
 193
 194                         list.Insert (index, element);
 195                         modified = true;
 196                 }
 197
 198                 protected internal void BaseClear ()
 199                 {
 200                         if (IsReadOnly ())
 201                                 throw new ConfigurationErrorsException ("Collection is read only.");
 202
 203                         list.Clear ();
 204                         modified = true;
 205                 }
 206
 207                 protected internal ConfigurationElement BaseGet (int index)
 208                 {
 209                         return (ConfigurationElement) list [index];
 210                 }
 211
 212                 protected internal ConfigurationElement BaseGet (object key)
 213                 {
 214                         int index = IndexOfKey (key);
 215                         if (index != -1) return (ConfigurationElement) list [index];
 216                         else return null;
 217                 }
 218
 219                 protected internal object[] BaseGetAllKeys ()
 220                 {
 221                         object[] keys = new object [list.Count];
 222                         for (int n=0; n<list.Count; n++)
 223                                 keys [n] = BaseGetKey (n);
 224                         return keys;
 225                 }
 226
 227                 protected internal object BaseGetKey (int index)
 228                 {
 229                         if (index < 0 || index >= list.Count)
 230                                 throw new ConfigurationErrorsException (String.Format ("Index {0} is out of range", index));
 231
 232                         return GetElementKey ((ConfigurationElement) list[index]).ToString ();
 233                 }
 234
 235                 protected int BaseIndexOf (ConfigurationElement element)
 236                 {
 237                         return list.IndexOf (element);
 238                 }
 239
 240                 int IndexOfKey (object key)
 241                 {
 242                         for (int n=0; n<list.Count; n++) {
 243                                 if (CompareKeys (GetElementKey ((ConfigurationElement) list[n]), key))
 244                                         return n;
 245                         }
 246                         return -1;
 247                 }
 248
 249                 protected internal bool BaseIsRemoved (object key)
 250                 {
 251                         if (removed == null)
 252                                 return false;
 253                         foreach (ConfigurationElement elem in removed) {
 254                                 if (CompareKeys (GetElementKey (elem), key))
 255                                         return true;
 256                         }
 257                         return false;
 258                 }
 259
 260                 protected internal void BaseRemove (object key)
 261                 {
 262                         if (IsReadOnly ())
 263                                 throw new ConfigurationErrorsException ("Collection is read only.");
 264
 265                         int index = IndexOfKey (key);
 266                         if (index != -1) {
 267                                 BaseRemoveAt (index);
 268                                 modified = true;
 269                         }
 270                 }
 271
 272                 protected internal void BaseRemoveAt (int index)
 273                 {
 274                         if (IsReadOnly ())
 275                                 throw new ConfigurationErrorsException ("Collection is read only.");
 276
 277                         ConfigurationElement elem = (ConfigurationElement) list [index];
 278                         if (!IsElementRemovable (elem))
 279                                 throw new ConfigurationErrorsException ("Element can't be removed from element collection.");
 280
 281                         if (inherited != null && inherited.Contains (elem))
 282                                 throw new ConfigurationErrorsException ("Inherited items can't be removed.");
 283
 284                         list.RemoveAt (index);
 285                         modified = true;
 286                 }
 287
 288                 bool CompareKeys (object key1, object key2)
 289                 {
 290                         if (comparer != null)
 291                                 return comparer.Compare (key1, key2) == 0;
 292                         else
 293                                 return object.Equals (key1, key2);
 294                 }
 295
 296                 public void CopyTo (ConfigurationElement[] array, int index)
 297                 {
 298                         list.CopyTo (array, index);
 299                 }
 300
 301                 protected abstract ConfigurationElement CreateNewElement ();
 302
 303                 protected virtual ConfigurationElement CreateNewElement (string elementName)
 304                 {
 305                         return CreateNewElement ();
 306                 }
 307
 308                 ConfigurationElement CreateNewElementInternal (string elementName)
 309                 {
 310                         ConfigurationElement elem;
 311                         if (elementName == null)
 312                                 elem = CreateNewElement ();
 313                         else
 314                                 elem = CreateNewElement (elementName);
 315                         elem.Init ();
 316                         return elem;
 317                 }
 318
 319                 public override bool Equals (object compareTo)
 320                 {
 321                         ConfigurationElementCollection other = compareTo as ConfigurationElementCollection;
 322                         if (other == null) return false;
 323                         if (GetType() != other.GetType()) return false;
 324                         if (Count != other.Count) return false;
 325
 326                         for (int n=0; n<Count; n++) {
 327                                 if (!BaseGet (n).Equals (other.BaseGet (n)))
 328                                         return false;
 329                         }
 330                         return true;
 331                 }
 332
 333                 protected abstract object GetElementKey (ConfigurationElement element);
 334
 335                 public override int GetHashCode ()
 336                 {
 337                         int code = 0;
 338                         for (int n=0; n<Count; n++)
 339                                 code += BaseGet (n).GetHashCode ();
 340                         return code;
 341                 }
 342
 343                 void ICollection.CopyTo (Array arr, int index)
 344                 {
 345                         list.CopyTo (arr, index);
 346                 }
 347
 348                 public IEnumerator GetEnumerator ()
 349                 {
 350                         return list.GetEnumerator ();
 351                 }
 352
 353                 protected virtual bool IsElementName (string elementName)
 354                 {
 355                         return false;
 356                 }
 357
 358                 protected virtual bool IsElementRemovable (ConfigurationElement element)
 359                 {
 360                         return !IsReadOnly ();
 361                 }
 362
 363                 protected internal override bool IsModified ()
 364                 {
 365                         return modified;
 366                 }
 367
 368                 [MonoTODO]
 369                 public override bool IsReadOnly ()
 370                 {
 371                         return base.IsReadOnly ();
 372                 }
 373
 374                 internal override bool HasValues ()
 375                 {
 376                         return list.Count > 0;
 377                 }
 378
 379                 protected internal override void Reset (ConfigurationElement parentElement)
 380                 {
 381                         bool basic = IsBasic;
 382
 383                         ConfigurationElementCollection parent = (ConfigurationElementCollection) parentElement;
 384                         for (int n=0; n<parent.Count; n++)
 385                         {
 386                                 ConfigurationElement parentItem = parent.BaseGet (n);
 387                                 ConfigurationElement item = CreateNewElementInternal (null);
 388                                 item.Reset (parentItem);
 389                                 BaseAdd (item);
 390
 391                                 if (basic) {
 392                                         if (inherited == null)
 393                                                 inherited = new ArrayList ();
 394                                         inherited.Add (item);
 395                                 }
 396                         }
 397                         if (IsAlternate)
 398                                 inheritedLimitIndex = 0;
 399                         else
 400                                 inheritedLimitIndex = Count - 1;
 401                         modified = false;
 402                 }
 403
 404                 protected internal override void ResetModified ()
 405                 {
 406                         modified = false;
 407                 }
 408
 409                 [MonoTODO]
 410                 protected internal override void SetReadOnly ()
 411                 {
 412                         base.SetReadOnly ();
 413                 }
 414
 415                 protected internal override bool SerializeElement (XmlWriter writer, bool serializeCollectionKey)
 416                 {
 417                         if (serializeCollectionKey) {
 418                                 return base.SerializeElement (writer, serializeCollectionKey);
 419                         }
 420
 421                         bool wroteData = false;
 422
 423                         if (IsBasic)
 424                         {
 425                                 for (int n=0; n<list.Count; n++) {
 426                                         ConfigurationElement elem = (ConfigurationElement) list [n];
 427                                         if (ElementName != string.Empty)
 428                                                 wroteData = elem.SerializeToXmlElement (writer, ElementName) || wroteData;
 429                                         else
 430                                                 wroteData = elem.SerializeElement (writer, false) || wroteData;
 431                                 }
 432                         }
 433                         else
 434                         {
 435                                 if (emitClear) {
 436                                         writer.WriteElementString (clearElementName, "");
 437                                         wroteData = true;
 438                                 }
 439
 440                                 if (removed != null) {
 441                                         for (int n=0; n<removed.Count; n++) {
 442                                                 writer.WriteStartElement (removeElementName);
 443                                                 ((ConfigurationElement)removed[n]).SerializeElement (writer, true);
 444                                                 writer.WriteEndElement ();
 445                                         }
 446                                         wroteData = wroteData || removed.Count > 0;
 447                                 }
 448
 449                                 for (int n=0; n<list.Count; n++) {
 450                                         ConfigurationElement elem = (ConfigurationElement) list [n];
 451                                         elem.SerializeToXmlElement (writer, addElementName);
 452                                 }
 453
 454                                 wroteData = wroteData || list.Count > 0;
 455                         }
 456                         return wroteData;
 457                 }
 458
 459                 protected override bool OnDeserializeUnrecognizedElement (string elementName, XmlReader reader)
 460                 {
 461                         if (IsBasic)
 462                         {
 463                                 ConfigurationElement elem = null;
 464
 465                                 if (elementName == ElementName)
 466                                         elem = CreateNewElementInternal (null);
 467                                 if (IsElementName (elementName))
 468                                         elem = CreateNewElementInternal (elementName);
 469
 470                                 if (elem != null) {
 471                                         elem.DeserializeElement (reader, false);
 472                                         BaseAdd (elem);
 473                                         modified = false;
 474                                         return true;
 475                                 }
 476                         }
 477                         else {
 478                                 if (elementName == clearElementName) {
 479                                         reader.MoveToContent ();
 480                                         if (reader.MoveToNextAttribute ())
 481                                                 throw new ConfigurationErrorsException ("Unrecognized attribute '" + reader.LocalName + "'.");
 482                                         reader.MoveToElement ();
 483                                         reader.Skip ();
 484                                         BaseClear ();
 485                                         emitClear = true;
 486                                         modified = false;
 487                                         return true;
 488                                 }
 489                                 else if (elementName == removeElementName) {
 490                                         ConfigurationElement elem = CreateNewElementInternal (null);
 491                                         ConfigurationRemoveElement removeElem = new ConfigurationRemoveElement (elem, this);
 492                                         removeElem.DeserializeElement (reader, true);
 493                                         BaseRemove (removeElem.KeyValue);
 494                                         modified = false;
 495                                         return true;
 496                                 }
 497                                 else if (elementName == addElementName) {
 498                                         ConfigurationElement elem = CreateNewElementInternal (null);
 499                                         elem.DeserializeElement (reader, false);
 500                                         BaseAdd (elem);
 501                                         modified = false;
 502                                         return true;
 503                                 }
 504                         }
 505
 506                         return false;
 507                 }
 508
 509                 protected internal override void Unmerge (ConfigurationElement sourceElement, ConfigurationElement parentElement, ConfigurationSaveMode updateMode)
 510                 {
 511                         ConfigurationElementCollection source = (ConfigurationElementCollection) sourceElement;
 512                         ConfigurationElementCollection parent = (ConfigurationElementCollection) parentElement;
 513
 514                         for (int n=0; n<source.Count; n++) {
 515                                 ConfigurationElement sitem = source.BaseGet (n);
 516                                 object key = source.GetElementKey (sitem);
 517                                 ConfigurationElement pitem = parent != null ? parent.BaseGet (key) as ConfigurationElement : null;
 518                                 if (pitem != null && updateMode != ConfigurationSaveMode.Full) {
 519                                         ConfigurationElement nitem = CreateNewElementInternal (null);
 520                                         nitem.Unmerge (sitem, pitem, ConfigurationSaveMode.Minimal);
 521                                         if (nitem.HasValues ())
 522                                                 BaseAdd (nitem);
 523                                 }
 524                                 else {
 525                                         ConfigurationElement nitem = CreateNewElementInternal (null);
 526                                         nitem.Unmerge (sitem, null, ConfigurationSaveMode.Full);
 527                                         BaseAdd (nitem);
 528                                 }
 529                         }
 530
 531                         if (updateMode == ConfigurationSaveMode.Full)
 532                                 EmitClear = true;
 533                         else if (parent != null) {
 534                                 for (int n=0; n<parent.Count; n++) {
 535                                         ConfigurationElement pitem = parent.BaseGet (n);
 536                                         object key = parent.GetElementKey (pitem);
 537                                         if (source.IndexOfKey (key) == -1) {
 538                                                 if (removed == null) removed = new ArrayList ();
 539                                                 removed.Add (pitem);
 540                                         }
 541                                 }
 542                         }
 543                 }
 544
 545                 #endregion // Methods
 546         }
 547 }
 548
 549 #endif