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XmlSchemaCollection Class

Note: This API is now obsolete.

Contains a cache of XML Schema definition language (XSD) and XML-Data Reduced (XDR) schemas. The XmlSchemaCollection class class is obsolete. Use XmlSchemaSet instead.


Namespace:  System.Xml.Schema
Assembly:  System.Xml (in System.Xml.dll)

[ObsoleteAttribute("Use System.Xml.Schema.XmlSchemaSet for schema compilation and validation.")]
public sealed class XmlSchemaCollection : ICollection, 

The XmlSchemaCollection type exposes the following members.

Public methodXmlSchemaCollection()Initializes a new instance of the XmlSchemaCollection class.
Public methodXmlSchemaCollection(XmlNameTable)Initializes a new instance of the XmlSchemaCollection class with the specified XmlNameTable. The XmlNameTable is used when loading schemas.

Public propertyCountGets the number of namespaces defined in this collection.
Public propertyItemGets the XmlSchema associated with the given namespace URI.
Public propertyNameTableGets the default XmlNameTable used by the XmlSchemaCollection when loading new schemas.

Public methodAdd(XmlSchema)Adds the XmlSchema to the collection.
Public methodAdd(XmlSchemaCollection)Adds all the namespaces defined in the given collection (including their associated schemas) to this collection.
Public methodAdd(String, String)Adds the schema located by the given URL into the schema collection.
Public methodAdd(String, XmlReader)Adds the schema contained in the XmlReader to the schema collection.
Public methodAdd(XmlSchema, XmlResolver)Adds the XmlSchema to the collection. The specified XmlResolver is used to resolve any external references.
Public methodAdd(String, XmlReader, XmlResolver)Adds the schema contained in the XmlReader to the schema collection. The specified XmlResolver is used to resolve any external resources.
Public methodContains(String)Gets a value indicating whether a schema with the specified namespace is in the collection.
Public methodContains(XmlSchema)Gets a value indicating whether the targetNamespace of the specified XmlSchema is in the collection.
Public methodCopyToCopies all the XmlSchema objects from this collection into the given array starting at the given index.
Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetEnumeratorProvides support for the "for each" style iteration over the collection of schemas.
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

Public eventValidationEventHandlerSets an event handler for receiving information about the XDR and XML schema validation errors.

Public Extension MethodAsParallelEnables parallelization of a query. (Defined by ParallelEnumerable.)
Public Extension MethodAsQueryableConverts an IEnumerable to an IQueryable. (Defined by Queryable.)
Public Extension MethodCast<TResult>Converts the elements of an IEnumerable to the specified type. (Defined by Enumerable.)
Public Extension MethodOfType<TResult>Filters the elements of an IEnumerable based on a specified type. (Defined by Enumerable.)

Explicit interface implemetationPrivate methodICollection.CopyToFor a description of this member, see XmlSchemaCollection.CopyTo.
Explicit interface implemetationPrivate propertyICollection.CountFor a description of this member, see XmlSchemaCollection.Count.
Explicit interface implemetationPrivate propertyICollection.IsSynchronizedFor a description of this member, see ICollectionIsSynchronized().
Explicit interface implemetationPrivate propertyICollection.SyncRootFor a description of this member, see ICollectionSyncRoot().
Explicit interface implemetationPrivate methodIEnumerable.GetEnumeratorFor a description of this member, see XmlSchemaCollection.GetEnumerator.

Schemas are loaded using the Add method, at which time the schema is associated with a namespace Uniform Resource Identifier (URI). For XML Schemas, this will typically be the targetNamespace property of the schema.

Although this class stores both XML Schemas and XDR schemas, any method and property that takes or returns an XmlSchema applies to XML Schemas only.

This version of the product supports the World Wide Web Consortium (W3C) XML Schema recommendation located at and An XML Schema must reference the W3C Schema namespace in its schema element. See the Add method for an example.

XmlSchemaCollection can be used by XmlValidatingReader for efficient data validation.

Important noteImportant

The XmlSchemaCollection class is obsolete in the Microsoft .NET Framework version 2.0 and has been replaced by the XmlSchemaSet class.

The following example validates an XML document using the XmlSchemaCollection.

using System;
using System.Xml;
using System.Xml.Schema;
using System.IO;

public class ValidXSD {

  public static void Main() {
    XmlSchemaCollection sc = new XmlSchemaCollection();
    sc.ValidationEventHandler += new ValidationEventHandler(ValidationCallBack);
    sc.Add(null, "books.xsd");

    if(sc.Count > 0)
      XmlTextReader tr = new XmlTextReader("notValidXSD.xml");
      XmlValidatingReader rdr = new XmlValidatingReader(tr);

      rdr.ValidationType = ValidationType.Schema;
      rdr.ValidationEventHandler += new ValidationEventHandler(ValidationCallBack);
      while (rdr.Read());


  private static void ValidationCallBack(object sender, ValidationEventArgs e) {
    Console.WriteLine("Validation Error: {0}", e.Message);

.NET Framework

Supported in: 1.1, 1.0
Obsolete (compiler warning) in 4
Obsolete (compiler warning) in 3.5
Obsolete (compiler warning) in 3.5 SP1
Obsolete (compiler warning) in 3.0
Obsolete (compiler warning) in 3.0 SP1
Obsolete (compiler warning) in 3.0 SP2
Obsolete (compiler warning) in 2.0
Obsolete (compiler warning) in 2.0 SP1
Obsolete (compiler warning) in 2.0 SP2

.NET Framework Client Profile

Obsolete (compiler warning) in 4
Obsolete (compiler warning) in 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.