mcs/class/System.XML/System.Xml.Schema/XmlSchemaAttribute.cs

   1 //\r
   2 // System.Xml.Schema.XmlSchemaAttribute.cs\r
   3 //\r
   4 // Authors:\r
   5 //      Dwivedi, Ajay kumar  Adwiv@Yahoo.com\r
   6 //      Enomoto, Atsushi     ginga@kit.hi-ho.ne.jp\r
   7 //\r
   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 using System;\r
  30 using System.Xml;\r
  31 using System.ComponentModel;\r
  32 using System.Xml.Serialization;\r
  33 \r
  34 namespace System.Xml.Schema\r
  35 {\r
  36         /// <summary>\r
  37         /// Summary description for XmlSchemaAttribute.\r
  38         /// </summary>\r
  39         public class XmlSchemaAttribute : XmlSchemaAnnotated\r
  40         {\r
  41                 private object attributeType;\r
  42 #if NET_2_0\r
  43                 private XmlSchemaSimpleType attributeSchemaType;\r
  44 #endif\r
  45                 private string defaultValue;\r
  46                 private string fixedValue;\r
  47                 private string validatedDefaultValue;\r
  48                 private string validatedFixedValue;\r
  49                 private XmlSchemaForm form;\r
  50                 private string name;\r
  51                 private string targetNamespace;\r
  52                 private XmlQualifiedName qualifiedName;\r
  53                 private XmlQualifiedName refName;\r
  54                 private XmlSchemaSimpleType schemaType;\r
  55                 private XmlQualifiedName schemaTypeName;\r
  56                 private XmlSchemaUse use;\r
  57                 private XmlSchemaUse validatedUse;\r
  58                 //Compilation fields\r
  59                 internal bool ParentIsSchema = false;\r
  60                 private XmlSchemaAttribute referencedAttribute;\r
  61                 const string xmlname = "attribute";\r
  62 \r
  63                 public XmlSchemaAttribute()\r
  64                 {\r
  65                         //LAMESPEC: Docs says the default is optional.\r
  66                         //Whereas the MS implementation has default None.\r
  67                         form    = XmlSchemaForm.None;\r
  68                         use             = XmlSchemaUse.None;\r
  69                         schemaTypeName  = XmlQualifiedName.Empty;\r
  70                         qualifiedName   = XmlQualifiedName.Empty;\r
  71                         refName                 = XmlQualifiedName.Empty;\r
  72                 }\r
  73 \r
  74                 // Properties\r
  75                 #region Properties\r
  76 \r
  77                 [DefaultValue(null)]\r
  78                 [System.Xml.Serialization.XmlAttribute("default")]\r
  79                 public string DefaultValue \r
  80                 {\r
  81                         get{ return defaultValue;}\r
  82                         set\r
  83                         { // Default Value and fixed Value are mutually exclusive\r
  84                                 fixedValue = null;\r
  85                                 defaultValue = value;\r
  86                         }\r
  87                 }\r
  88 \r
  89                 [DefaultValue(null)]\r
  90                 [System.Xml.Serialization.XmlAttribute("fixed")]\r
  91                 public string FixedValue \r
  92                 {\r
  93                         get{ return fixedValue;}\r
  94                         set\r
  95                         { // Default Value and fixed Value are mutually exclusive\r
  96                                 defaultValue = null;\r
  97                                 fixedValue = value;\r
  98                         }\r
  99                 }\r
 100 \r
 101                 [DefaultValue(XmlSchemaForm.None)]\r
 102                 [System.Xml.Serialization.XmlAttribute("form")]\r
 103                 public XmlSchemaForm Form \r
 104                 {\r
 105                         get{ return form;}\r
 106                         set{ form = value;}\r
 107                 }\r
 108 \r
 109                 [System.Xml.Serialization.XmlAttribute("name")]\r
 110                 public string Name \r
 111                 {\r
 112                         get{ return name;}\r
 113                         set\r
 114                         {\r
 115                                 name  = value;\r
 116                         }\r
 117                 }\r
 118 \r
 119                 [System.Xml.Serialization.XmlAttribute("ref")]\r
 120                 public XmlQualifiedName RefName \r
 121                 {\r
 122                         get{ return refName;}\r
 123                         set\r
 124                         {\r
 125                                 refName = value; \r
 126                         }\r
 127                 }\r
 128                 \r
 129                 [System.Xml.Serialization.XmlAttribute("type")]\r
 130                 public XmlQualifiedName SchemaTypeName \r
 131                 {\r
 132                         get{ return schemaTypeName;}\r
 133                         set{ schemaTypeName = value;}\r
 134                 }\r
 135 \r
 136                 [XmlElement("simpleType")]\r
 137                 public XmlSchemaSimpleType SchemaType \r
 138                 {\r
 139                         get{ return schemaType;}\r
 140                         set{ schemaType = value;}\r
 141                 }\r
 142 \r
 143                 [DefaultValue(XmlSchemaUse.None)]\r
 144                 [System.Xml.Serialization.XmlAttribute("use")]\r
 145                 public XmlSchemaUse Use \r
 146                 {\r
 147                         get{ return use;}\r
 148                         set{ use = value;}\r
 149                 }\r
 150 \r
 151                 [XmlIgnore]\r
 152                 public XmlQualifiedName QualifiedName \r
 153                 {\r
 154                         get{ return qualifiedName;}\r
 155                 }\r
 156 \r
 157                 [XmlIgnore]\r
 158 #if NET_2_0\r
 159                 [Obsolete]\r
 160 #endif\r
 161                 public object AttributeType \r
 162                 {\r
 163                         get{\r
 164                                 if (referencedAttribute != null)\r
 165                                         return referencedAttribute.AttributeType;\r
 166                                 else\r
 167                                         return attributeType;\r
 168                         }\r
 169                 }\r
 170 \r
 171 #if NET_2_0\r
 172                 [XmlIgnore]\r
 173                 public XmlSchemaSimpleType AttributeSchemaType\r
 174                 {\r
 175                         get {\r
 176                                 if (referencedAttribute != null)\r
 177                                         return referencedAttribute.AttributeSchemaType;\r
 178                                 else\r
 179                                         return attributeSchemaType;\r
 180                         }\r
 181                 }\r
 182 #endif\r
 183 \r
 184                 // Post compilation default value (normalized)\r
 185                 internal string ValidatedDefaultValue\r
 186                 {\r
 187                         // DefaultValue can be overriden in case of ref.\r
 188                         get { return validatedDefaultValue; }\r
 189                 }\r
 190 \r
 191                 // Post compilation fixed value (normalized)\r
 192                 internal string ValidatedFixedValue \r
 193                 {\r
 194                         // FixedValue can be overriden in case of ref.\r
 195                         get { return validatedFixedValue; }\r
 196                 }\r
 197                 internal XmlSchemaUse ValidatedUse\r
 198                 {\r
 199                         get { return validatedUse; }\r
 200                 }\r
 201 \r
 202                 #endregion\r
 203 \r
 204                 /// <remarks>\r
 205                 /// For an attribute:\r
 206                 ///  a) If the parent is schema \r
 207                 ///             1-5             are from <xs:complexType name="topLevelAttribute"> in the Schema for Schema\r
 208                 ///             6-8             are from  "Constraints on XML Representations of Attribute Declarations"\r
 209                 ///             9-10    are from "Attribute Declaration Schema Component"\r
 210                 ///             11-16   are from "Constraints on Attribute Declaration Schema Components"\r
 211                 ///             1. ref  must be absent\r
 212                 ///             2. form must be absent\r
 213                 ///             3. use  must be absent\r
 214                 ///             4. name must be present and of type NCName\r
 215                 ///             5. *NO CHECK REQUIRED* Only simple types and annotation are allowed as content\r
 216                 ///             6. default and fixed must not both be present. \r
 217                 ///             7. *NO CHECK REQUIRED* If default and use are both present... (Not possible since use is absent)\r
 218                 ///             8. type and <simpleType> must not both be present.\r
 219                 ///             9. Target Namespace should be schema's targetnamespace or absent\r
 220                 ///             10. Type Definiton coressponds to <simpletype> element, or type value, or absent\r
 221                 ///             11. *TO UNDERSTAND* Missing Sub-components\r
 222                 ///             12. value constraint must be of the same datatype as of type\r
 223                 ///             13. if the type definition is ID then there should be no value constraint.\r
 224                 ///             14. name must not be xmlns\r
 225                 ///             15. Targetnamespace must not be xsi. This implies the target namespace of schema can't be xsi if toplevel attributes are used.\r
 226                 ///             16. *Exception to rule 15* inbuilt attributes: xsi:nil, xsi:type, xsi:schemaLocation, xsi: noNamespaceSchemaLocation\r
 227                 ///     b) If the parent is complextype and ref is not set\r
 228                 ///             1. name must be present and of type NCName.\r
 229                 ///             2. type and <simpleType> must not both be present.\r
 230                 ///             3. default and fixed must not both be present. \r
 231                 ///     4. If default and use are both present, use must have the ·actual value· optional.\r
 232                 ///             5. name must not be xmlns\r
 233                 ///             6. Targetnamespace must not be xsi.\r
 234                 ///             7. *Exception to rule 15* inbuilt attributes: xsi:nil, xsi:type, xsi:schemaLocation, xsi: noNamespaceSchemaLocation\r
 235                 ///             8. If form has actual value qualified or the schema's formdefault is qualified, targetnamespace\r
 236                 ///                is same as schema's target namespace, otherwise absent.\r
 237                 ///     c) if the parent is not schema and ref is set\r
 238                 ///             1. name must not be present\r
 239                 ///             2. all of <simpleType>, form and type must be absent. \r
 240                 ///             3. default and fixed must not both be present. \r
 241                 ///     4. If default and use are both present, use must have the ·actual value· optional.\r
 242                 /// </remarks>\r
 243                 internal override int Compile(ValidationEventHandler h, XmlSchema schema)\r
 244                 {\r
 245                         // If this is already compiled this time, simply skip.\r
 246                         if (this.IsComplied (schema.CompilationId))\r
 247                                 return 0;\r
 248 \r
 249 #if NET_2_0\r
 250                         if (schemaType != null)\r
 251                                 schemaType.Parent = this;\r
 252 #endif\r
 253 \r
 254                         errorCount = 0;\r
 255                         \r
 256                         if(ParentIsSchema || isRedefineChild)//a\r
 257                         {\r
 258                                 if(RefName!= null && !RefName.IsEmpty) // a.1\r
 259                                         error(h,"ref must be absent in the top level <attribute>");\r
 260                                 \r
 261                                 if(Form != XmlSchemaForm.None)  // a.2\r
 262                                         error(h,"form must be absent in the top level <attribute>");\r
 263                                 \r
 264                                 if(Use != XmlSchemaUse.None)            // a.3\r
 265                                         error(h,"use must be absent in the top level <attribute>");\r
 266 \r
 267                                 targetNamespace = schema.TargetNamespace;\r
 268 \r
 269                                 CompileCommon (h, schema, true);\r
 270                         }\r
 271                         else // local\r
 272                         {\r
 273                                 // Q:How to Use of AttributeFormDefault????\r
 274                                 // A:Global attribute cannot be defined locally\r
 275                                 if(RefName == null || RefName.IsEmpty)\r
 276                                 {\r
 277                                         if(form == XmlSchemaForm.Qualified || (form == XmlSchemaForm.None && schema.AttributeFormDefault == XmlSchemaForm.Qualified))\r
 278                                                 this.targetNamespace = schema.TargetNamespace;\r
 279                                         else\r
 280                                                 this.targetNamespace = "";\r
 281 \r
 282                                         CompileCommon(h, schema, true);\r
 283                                 }\r
 284                                 else\r
 285                                 {\r
 286                                         if(this.name != null)\r
 287                                                 error(h,"name must be absent if ref is present");\r
 288                                         if(this.form != XmlSchemaForm.None)\r
 289                                                 error(h,"form must be absent if ref is present");\r
 290                                         if(this.schemaType != null)\r
 291                                                 error(h,"simpletype must be absent if ref is present");\r
 292                                         if(this.schemaTypeName != null && !this.schemaTypeName.IsEmpty)\r
 293                                                 error(h,"type must be absent if ref is present");\r
 294 \r
 295                                         CompileCommon(h, schema, false);\r
 296                                 }\r
 297                         }\r
 298 \r
 299                         this.CompilationId = schema.CompilationId;\r
 300                         return errorCount;\r
 301                 }\r
 302                 \r
 303                 private void CompileCommon(ValidationEventHandler h, XmlSchema schema, bool refIsNotPresent)\r
 304                 {\r
 305                         if(refIsNotPresent)\r
 306                         {\r
 307                                 if(Name == null)        //a.4, b.1, \r
 308                                         error(h,"Required attribute name must be present");\r
 309                                 else if(!XmlSchemaUtil.CheckNCName(Name)) // a.4.2, b1.2\r
 310                                         error(h,"attribute name must be NCName");\r
 311                                 else if(Name == "xmlns") // a.14 , b5\r
 312                                         error(h,"attribute name must not be xmlns");\r
 313                                 else\r
 314                                         qualifiedName = new XmlQualifiedName(Name, targetNamespace);\r
 315 \r
 316                                 if(SchemaType != null)\r
 317                                 {\r
 318                                         if(SchemaTypeName != null && !SchemaTypeName.IsEmpty) // a.8\r
 319                                                 error(h,"attribute can't have both a type and <simpleType> content");\r
 320 \r
 321                                         errorCount += SchemaType.Compile(h, schema); \r
 322                                 }\r
 323 \r
 324                                 if(SchemaTypeName != null && !XmlSchemaUtil.CheckQName(SchemaTypeName))\r
 325                                         error(h,SchemaTypeName+" is not a valid QName");\r
 326                         }\r
 327                         else\r
 328                         {\r
 329                                 if(RefName == null || RefName.IsEmpty) \r
 330                                         throw new InvalidOperationException ("Error: Should Never Happen. refname must be present");\r
 331                                 else\r
 332                                         qualifiedName = RefName;\r
 333                         }\r
 334 \r
 335                         if(schema.TargetNamespace == XmlSchema.InstanceNamespace && Name != "nil" && Name != "type" \r
 336                                 && Name != "schemaLocation" && Name != "noNamespaceSchemaLocation") // a.15, a.16\r
 337                                 error(h,"targetNamespace can't be " + XmlSchema.InstanceNamespace);\r
 338 \r
 339                         if(DefaultValue != null && FixedValue != null) // a.6, b.3, c.3\r
 340                                 error(h,"default and fixed must not both be present in an Attribute");\r
 341 \r
 342                         if(DefaultValue != null && Use != XmlSchemaUse.None && Use != XmlSchemaUse.Optional)\r
 343                                 error(h,"if default is present, use must be optional");\r
 344 \r
 345                         XmlSchemaUtil.CompileID(Id, this, schema.IDCollection, h);\r
 346                 }\r
 347 \r
 348                 /// <summary>\r
 349                 /// Schema Component: \r
 350                 ///                     QName, SimpleType, Scope, Default|Fixed, annotation\r
 351                 /// </summary>\r
 352                 internal override int Validate(ValidationEventHandler h, XmlSchema schema)\r
 353                 {\r
 354                         if(IsValidated (schema.ValidationId))\r
 355                                 return errorCount;\r
 356 \r
 357                         // -- Attribute Declaration Schema Component --\r
 358                         // {name}, {target namespace} -> QualifiedName. Already Compile()d.\r
 359                         // {type definition} -> attributeType. From SchemaType or SchemaTypeName.\r
 360                         // {scope} -> ParentIsSchema | isRedefineChild.\r
 361                         // {value constraint} -> ValidatedFixedValue, ValidatedDefaultValue.\r
 362                         // {annotation}\r
 363                         // -- Attribute Use Schema Component --\r
 364                         // {required}\r
 365                         // {attribute declaration}\r
 366                         // {value constraint}\r
 367 \r
 368                         // First, fill type information for type reference\r
 369                         if (SchemaType != null) {\r
 370                                 SchemaType.Validate (h, schema);\r
 371                                 attributeType = SchemaType;\r
 372                         }\r
 373                         else if (SchemaTypeName != null && SchemaTypeName != XmlQualifiedName.Empty)\r
 374                         {\r
 375                                 // If type is null, then it is missing sub components .\r
 376                                 XmlSchemaType type = schema.SchemaTypes [SchemaTypeName] as XmlSchemaType;\r
 377                                 if (type is XmlSchemaComplexType)\r
 378                                         error(h,"An attribute can't have complexType Content");\r
 379                                 else if (type != null) {        // simple type\r
 380                                         errorCount += type.Validate (h, schema);\r
 381                                         attributeType = type;\r
 382                                 }\r
 383                                 else if (SchemaTypeName == XmlSchemaComplexType.AnyTypeName)\r
 384                                         attributeType = XmlSchemaComplexType.AnyType;
 385                                 else if (XmlSchemaUtil.IsBuiltInDatatypeName (SchemaTypeName)) {\r
 386                                         attributeType = XmlSchemaDatatype.FromName (SchemaTypeName);\r
 387                                         if (attributeType == null)\r
 388                                                 error (h, "Invalid xml schema namespace datatype was specified.");\r
 389                                 }\r
 390                                 // otherwise, it might be missing sub components.\r
 391                                 else if (!schema.IsNamespaceAbsent (SchemaTypeName.Namespace))\r
 392                                         error (h, "Referenced schema type " + SchemaTypeName + " was not found in the corresponding schema.");\r
 393                         }\r
 394 \r
 395                         // Then, fill type information for the type references for the referencing attributes\r
 396                         if (RefName != null && RefName != XmlQualifiedName.Empty)\r
 397                         {\r
 398                                 referencedAttribute = schema.Attributes [RefName] as XmlSchemaAttribute;\r
 399                                 // If el is null, then it is missing sub components .\r
 400                                 if (referencedAttribute != null)\r
 401                                         errorCount += referencedAttribute.Validate (h, schema);\r
 402                                 // otherwise, it might be missing sub components.\r
 403                                 else if (!schema.IsNamespaceAbsent (RefName.Namespace))\r
 404                                         error (h, "Referenced attribute " + RefName + " was not found in the corresponding schema.");\r
 405                         }\r
 406 \r
 407                         if (attributeType == null)\r
 408                                 attributeType = XmlSchemaSimpleType.AnySimpleType;\r
 409 \r
 410                         // Validate {value constraints}\r
 411                         if (defaultValue != null || fixedValue != null) {\r
 412                                 XmlSchemaDatatype datatype = attributeType as XmlSchemaDatatype;\r
 413                                 if (datatype == null)\r
 414                                         datatype = ((XmlSchemaSimpleType) attributeType).Datatype;\r
 415                                 if (datatype.TokenizedType == XmlTokenizedType.QName)\r
 416                                         error (h, "By the defection of the W3C XML Schema specification, it is impossible to supply QName default or fixed values.");\r
 417                                 else {\r
 418                                         try {\r
 419                                                 if (defaultValue != null) {\r
 420                                                         validatedDefaultValue = datatype.Normalize (defaultValue);\r
 421                                                         datatype.ParseValue (validatedDefaultValue, null, null);\r
 422                                                 }\r
 423                                         } catch (Exception ex) {\r
 424                                                 // FIXME: This is not a good way to handle exception.\r
 425                                                 error (h, "The Attribute's default value is invalid with its type definition.", ex);\r
 426                                         }\r
 427                                         try {\r
 428                                                 if (fixedValue != null) {\r
 429                                                         validatedFixedValue = datatype.Normalize (fixedValue);\r
 430                                                         datatype.ParseValue (validatedFixedValue, null, null);\r
 431                                                 }\r
 432                                         } catch (Exception ex) {\r
 433                                                 // FIXME: This is not a good way to handle exception.\r
 434                                                 error (h, "The Attribute's fixed value is invalid with its type definition.", ex);\r
 435                                         }\r
 436                                 }\r
 437                         }\r
 438                         if (Use == XmlSchemaUse.None)\r
 439                                 validatedUse = XmlSchemaUse.Optional;\r
 440                         else\r
 441                                 validatedUse = Use;\r
 442 \r
 443 #if NET_2_0\r
 444                         attributeSchemaType = attributeType as XmlSchemaSimpleType;\r
 445                         if (attributeSchemaType == null)\r
 446                                 attributeSchemaType = XmlSchemaType.GetBuiltInSimpleType (((XmlSchemaDatatype) attributeType).TypeCode);\r
 447 #endif\r
 448 \r
 449                         ValidationId = schema.ValidationId;\r
 450                         return errorCount;\r
 451                 }\r
 452 \r
 453                 //<attribute\r
 454                 //  default = string\r
 455                 //  fixed = string\r
 456                 //  form = (qualified | unqualified)\r
 457                 //  id = ID\r
 458                 //  name = NCName\r
 459                 //  ref = QName\r
 460                 //  type = QName\r
 461                 //  use = (optional | prohibited | required) : optional\r
 462                 //  {any attributes with non-schema namespace . . .}>\r
 463                 //  Content: (annotation?, (simpleType?))\r
 464                 //</attribute>\r
 465                 internal static XmlSchemaAttribute Read(XmlSchemaReader reader, ValidationEventHandler h)\r
 466                 {\r
 467                         XmlSchemaAttribute attribute = new XmlSchemaAttribute();\r
 468                         reader.MoveToElement();\r
 469 \r
 470                         if(reader.NamespaceURI != XmlSchema.Namespace || reader.LocalName != xmlname)\r
 471                         {\r
 472                                 error(h,"Should not happen :1: XmlSchemaAttribute.Read, name="+reader.Name,null);\r
 473                                 reader.SkipToEnd();\r
 474                                 return null;\r
 475                         }\r
 476 \r
 477                         attribute.LineNumber = reader.LineNumber;\r
 478                         attribute.LinePosition = reader.LinePosition;\r
 479                         attribute.SourceUri = reader.BaseURI;\r
 480 \r
 481                         while(reader.MoveToNextAttribute())\r
 482                         {\r
 483                                 if(reader.Name == "default")\r
 484                                 {\r
 485                                         attribute.defaultValue = reader.Value;\r
 486                                 }\r
 487                                 else if(reader.Name == "fixed")\r
 488                                 {\r
 489                                         attribute.fixedValue = reader.Value;\r
 490                                 }\r
 491                                 else if(reader.Name == "form")\r
 492                                 {\r
 493                                         Exception innerex;\r
 494                                         attribute.form = XmlSchemaUtil.ReadFormAttribute(reader,out innerex);\r
 495                                         if(innerex != null)\r
 496                                                 error(h, reader.Value + " is not a valid value for form attribute", innerex);\r
 497                                 }\r
 498                                 else if(reader.Name == "id")\r
 499                                 {\r
 500                                         attribute.Id = reader.Value;\r
 501                                 }\r
 502                                 else if(reader.Name == "name")\r
 503                                 {\r
 504                                         attribute.name = reader.Value;\r
 505                                 }\r
 506                                 else if(reader.Name == "ref")\r
 507                                 {\r
 508                                         Exception innerex;\r
 509                                         attribute.refName = XmlSchemaUtil.ReadQNameAttribute(reader,out innerex);\r
 510                                         if(innerex != null)\r
 511                                                 error(h, reader.Value + " is not a valid value for ref attribute",innerex);\r
 512                                 }\r
 513                                 else if(reader.Name == "type")\r
 514                                 {\r
 515                                         Exception innerex;\r
 516                                         attribute.schemaTypeName = XmlSchemaUtil.ReadQNameAttribute(reader,out innerex);\r
 517                                         if(innerex != null)\r
 518                                                 error(h, reader.Value + " is not a valid value for type attribute",innerex);\r
 519                                 }\r
 520                                 else if(reader.Name == "use")\r
 521                                 {\r
 522                                         Exception innerex;\r
 523                                         attribute.use = XmlSchemaUtil.ReadUseAttribute(reader,out innerex);\r
 524                                         if(innerex != null)\r
 525                                                 error(h, reader.Value + " is not a valid value for use attribute", innerex);\r
 526                                 }\r
 527                                 else if((reader.NamespaceURI == "" && reader.Name != "xmlns") || reader.NamespaceURI == XmlSchema.Namespace)\r
 528                                 {\r
 529                                         error(h,reader.Name + " is not a valid attribute for attribute",null);\r
 530                                 }\r
 531                                 else\r
 532                                 {\r
 533                                         XmlSchemaUtil.ReadUnhandledAttribute(reader,attribute);\r
 534                                 }\r
 535                         }\r
 536                         \r
 537                         reader.MoveToElement();\r
 538                         if(reader.IsEmptyElement)\r
 539                                 return attribute;\r
 540 \r
 541                         //  Content: (annotation?, (simpleType?))\r
 542                         int level = 1;\r
 543                         while(reader.ReadNextElement())\r
 544                         {\r
 545                                 if(reader.NodeType == XmlNodeType.EndElement)\r
 546                                 {\r
 547                                         if(reader.LocalName != xmlname)\r
 548                                                 error(h,"Should not happen :2: XmlSchemaAttribute.Read, name="+reader.Name,null);\r
 549                                         break;\r
 550                                 }\r
 551                                 if(level <= 1 && reader.LocalName == "annotation")\r
 552                                 {\r
 553                                         level = 2; //Only one annotation\r
 554                                         XmlSchemaAnnotation annotation = XmlSchemaAnnotation.Read(reader,h);\r
 555                                         if(annotation != null)\r
 556                                                 attribute.Annotation = annotation;\r
 557                                         continue;\r
 558                                 }\r
 559                                 if(level <=2 && reader.LocalName == "simpleType")\r
 560                                 {\r
 561                                         level = 3;\r
 562                                         XmlSchemaSimpleType stype = XmlSchemaSimpleType.Read(reader,h);\r
 563                                         if(stype != null)\r
 564                                                 attribute.schemaType = stype;\r
 565                                         continue;\r
 566                                 }\r
 567                                 reader.RaiseInvalidElementError();\r
 568                         }\r
 569                         return attribute;\r
 570                 }\r
 571                 \r
 572         }\r
 573 }\r