XmlSchema Class

Definition

An in-memory representation of an XML Schema, as specified in the World Wide Web Consortium (W3C) XML Schema Part 1: Structures and XML Schema Part 2: Datatypes specifications.

public class XmlSchema : System.Xml.Schema.XmlSchemaObject
Inheritance

Examples

The following example creates a schema definition.

#using <mscorlib.dll>
#using <System.Xml.dll>

using namespace System;
using namespace System::Xml;
using namespace System::Xml::Schema;

class XmlSchemaExamples
{
public:
	static void Main()
	{

		XmlSchema^ schema = gcnew XmlSchema();

		// <xs:element name="cat" type="xs:string"/>
		XmlSchemaElement^ elementCat = gcnew XmlSchemaElement();
		schema->Items->Add(elementCat);
		elementCat->Name = "cat";
		elementCat->SchemaTypeName = gcnew XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema");

		// <xs:element name="dog" type="xs:string"/>
		XmlSchemaElement^ elementDog = gcnew XmlSchemaElement();
		schema->Items->Add(elementDog);
		elementDog->Name = "dog";
		elementDog->SchemaTypeName = gcnew XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema");

		// <xs:element name="redDog" substitutionGroup="dog" />
		XmlSchemaElement^ elementRedDog = gcnew XmlSchemaElement();
		schema->Items->Add(elementRedDog);
		elementRedDog->Name = "redDog";
		elementRedDog->SubstitutionGroup = gcnew XmlQualifiedName("dog");

		// <xs:element name="brownDog" substitutionGroup ="dog" />
		XmlSchemaElement^ elementBrownDog = gcnew XmlSchemaElement();
		schema->Items->Add(elementBrownDog);
		elementBrownDog->Name = "brownDog";
		elementBrownDog->SubstitutionGroup = gcnew XmlQualifiedName("dog");


		// <xs:element name="pets">
		XmlSchemaElement^ elementPets = gcnew XmlSchemaElement();
		schema->Items->Add(elementPets);
		elementPets->Name = "pets";

		// <xs:complexType>
		XmlSchemaComplexType^ complexType = gcnew XmlSchemaComplexType();
		elementPets->SchemaType = complexType;

		// <xs:choice minOccurs="0" maxOccurs="unbounded">
		XmlSchemaChoice^ choice = gcnew XmlSchemaChoice();
		complexType->Particle = choice;
		choice->MinOccurs = 0;
		choice->MaxOccursString = "unbounded";

		// <xs:element ref="cat"/>
		XmlSchemaElement^ catRef = gcnew XmlSchemaElement();
		choice->Items->Add(catRef);
		catRef->RefName = gcnew XmlQualifiedName("cat");

		// <xs:element ref="dog"/>
		XmlSchemaElement^ dogRef = gcnew XmlSchemaElement();
		choice->Items->Add(dogRef);
		dogRef->RefName = gcnew XmlQualifiedName("dog");

		XmlSchemaSet^ schemaSet = gcnew XmlSchemaSet();
		schemaSet->ValidationEventHandler += gcnew ValidationEventHandler(ValidationCallbackOne);
		schemaSet->Add(schema);
		schemaSet->Compile();

		XmlSchema^ compiledSchema;

		for each (XmlSchema^ schema1 in schemaSet->Schemas())
		{
			compiledSchema = schema1;
		}

		XmlNamespaceManager^ nsmgr = gcnew XmlNamespaceManager(gcnew NameTable());
		nsmgr->AddNamespace("xs", "http://www.w3.org/2001/XMLSchema");
		compiledSchema->Write(Console::Out, nsmgr);
	}

	static void ValidationCallbackOne(Object^ sender, ValidationEventArgs^ args)
	{
		Console::WriteLine(args->Message);
	}
};

int main()
{
	XmlSchemaExamples::Main();
	return 0;
};
using System;
using System.Xml;
using System.Xml.Schema;

class XMLSchemaExamples
{
    public static void Main()
    {

        XmlSchema schema = new XmlSchema();

        // <xs:element name="cat" type="xs:string"/>
        XmlSchemaElement elementCat = new XmlSchemaElement();
        schema.Items.Add(elementCat);
        elementCat.Name = "cat";
        elementCat.SchemaTypeName = new XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema");

        // <xs:element name="dog" type="xs:string"/>
        XmlSchemaElement elementDog = new XmlSchemaElement();
        schema.Items.Add(elementDog);
        elementDog.Name = "dog";
        elementDog.SchemaTypeName = new XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema");

        // <xs:element name="redDog" substitutionGroup="dog" />
        XmlSchemaElement elementRedDog = new XmlSchemaElement();
        schema.Items.Add(elementRedDog);
        elementRedDog.Name = "redDog";
        elementRedDog.SubstitutionGroup = new XmlQualifiedName("dog");

        // <xs:element name="brownDog" substitutionGroup ="dog" />
        XmlSchemaElement elementBrownDog = new XmlSchemaElement();
        schema.Items.Add(elementBrownDog);
        elementBrownDog.Name = "brownDog";
        elementBrownDog.SubstitutionGroup = new XmlQualifiedName("dog");


        // <xs:element name="pets">
        XmlSchemaElement elementPets = new XmlSchemaElement();
        schema.Items.Add(elementPets);
        elementPets.Name = "pets";

        // <xs:complexType>
        XmlSchemaComplexType complexType = new XmlSchemaComplexType();
        elementPets.SchemaType = complexType;

        // <xs:choice minOccurs="0" maxOccurs="unbounded">
        XmlSchemaChoice choice = new XmlSchemaChoice();
        complexType.Particle = choice;
        choice.MinOccurs = 0;
        choice.MaxOccursString = "unbounded";

        // <xs:element ref="cat"/>
        XmlSchemaElement catRef = new XmlSchemaElement();
        choice.Items.Add(catRef);
        catRef.RefName = new XmlQualifiedName("cat");

        // <xs:element ref="dog"/>
        XmlSchemaElement dogRef = new XmlSchemaElement();
        choice.Items.Add(dogRef);
        dogRef.RefName = new XmlQualifiedName("dog");

        XmlSchemaSet schemaSet = new XmlSchemaSet();
        schemaSet.ValidationEventHandler += new ValidationEventHandler(ValidationCallbackOne);
        schemaSet.Add(schema);
        schemaSet.Compile();

        XmlSchema compiledSchema = null;

        foreach (XmlSchema schema1 in schemaSet.Schemas())
        {
            compiledSchema = schema1;
        }

        XmlNamespaceManager nsmgr = new XmlNamespaceManager(new NameTable());
        nsmgr.AddNamespace("xs", "http://www.w3.org/2001/XMLSchema");
        compiledSchema.Write(Console.Out, nsmgr);
    }

    public static void ValidationCallbackOne(object sender, ValidationEventArgs args)
    {
        Console.WriteLine(args.Message);
    }
}
Option Explicit On
Option Strict On

Imports System
Imports System.Xml
Imports System.Xml.Schema

Class XMLSchemaExamples
    Public Shared Sub Main()
        Dim schema As New XmlSchema()

        ' <xs:element name="cat" type="xs:string"/>
        Dim elementCat As New XmlSchemaElement()
        schema.Items.Add(elementCat)
        elementCat.Name = "cat"
        elementCat.SchemaTypeName = New XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema")

        ' <xs:element name="dog" type="xs:string"/>
        Dim elementDog As New XmlSchemaElement()
        schema.Items.Add(elementDog)
        elementDog.Name = "dog"
        elementDog.SchemaTypeName = New XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema")

        ' <xs:element name="redDog" substitutionGroup="dog" />
        Dim elementRedDog As New XmlSchemaElement()
        schema.Items.Add(elementRedDog)
        elementRedDog.Name = "redDog"
        elementRedDog.SubstitutionGroup = New XmlQualifiedName("dog")

        ' <xs:element name="brownDog" substitutionGroup ="dog" />
        Dim elementBrownDog As New XmlSchemaElement()
        schema.Items.Add(elementBrownDog)
        elementBrownDog.Name = "brownDog"
        elementBrownDog.SubstitutionGroup = New XmlQualifiedName("dog")

        ' <xs:element name="pets">
        Dim elementPets As New XmlSchemaElement()
        schema.Items.Add(elementPets)
        elementPets.Name = "pets"

        ' <xs:complexType>
        Dim complexType As New XmlSchemaComplexType()
        elementPets.SchemaType = complexType

        ' <xs:choice minOccurs="0" maxOccurs="unbounded">
        Dim choice As New XmlSchemaChoice()
        complexType.Particle = choice
        choice.MinOccurs = 0
        choice.MaxOccursString = "unbounded"

        ' <xs:element ref="cat"/>
        Dim catRef As New XmlSchemaElement()
        choice.Items.Add(catRef)
        catRef.RefName = New XmlQualifiedName("cat")

        ' <xs:element ref="dog"/>
        Dim dogRef As New XmlSchemaElement()
        choice.Items.Add(dogRef)
        dogRef.RefName = New XmlQualifiedName("dog")

        Dim schemaSet As New XmlSchemaSet()
        AddHandler schemaSet.ValidationEventHandler, AddressOf ValidationCallbackOne

        schemaSet.Add(schema)
        schemaSet.Compile()

        Dim compiledSchema As XmlSchema = Nothing

        For Each schema1 As XmlSchema In schemaSet.Schemas()
            compiledSchema = schema1
        Next

        Dim nsmgr As New XmlNamespaceManager(New NameTable())
        nsmgr.AddNamespace("xs", "http://www.w3.org/2001/XMLSchema")
        compiledSchema.Write(Console.Out, nsmgr)


    End Sub 'Main


    Public Shared Sub ValidationCallbackOne(ByVal sender As Object, ByVal args As ValidationEventArgs)
        Console.WriteLine(args.Message)
    End Sub 'ValidationCallbackOne
End Class 'XMLSchemaExamples

The following XML file is generated for the preceding code example.


<?xml version="1.0" encoding="IBM437"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <xs:element name="cat" type="xs:string"/>
    <xs:element name="dog" type="xs:string"/>
    <xs:element name="redDog" type="xs:string" substitutionGroup="dog"/>
    <xs:element name="brownDog" type="xs:string" substitutionGroup ="dog" />

    <xs:element name="pets">
      <xs:complexType>
        <xs:choice minOccurs="0" maxOccurs="unbounded">
          <xs:element ref="cat"/>
          <xs:element ref="dog"/>
        </xs:choice>
      </xs:complexType>
    </xs:element>
</xs:schema>

Remarks

Important

  • Do not use schemas from unknown or untrusted sources or locations. Doing so will compromise the security of your code.
    • XML schemas (including inline schemas) are inherently vulnerable to denial of service attacks; do not accept them in untrusted scenarios.
    • Exceptions raised as a result of using the XmlSchema class, such as the XmlSchemaException class, may contain sensitive information that should not be exposed in untrusted scenarios. For example, the SourceUri property of an XmlSchemaException returns the URI path to the schema file that caused the exception. The SourceUri property should not be exposed in untrusted scenarios. Exceptions should be properly handled so this sensitive information is not exposed in untrusted scenarios.

Constructors

XmlSchema()

Initializes a new instance of the XmlSchema class.

Fields

InstanceNamespace

The XML schema instance namespace. This field is constant.

Namespace

The XML schema namespace. This field is constant.

Properties

AttributeFormDefault

Gets or sets the form for attributes declared in the target namespace of the schema.

AttributeGroups

Gets the post-schema-compilation value of all the global attribute groups in the schema.

Attributes

Gets the post-schema-compilation value for all the attributes in the schema.

BlockDefault

Gets or sets the blockDefault attribute which sets the default value of the block attribute on element and complex types in the targetNamespace of the schema.

ElementFormDefault

Gets or sets the form for elements declared in the target namespace of the schema.

Elements

Gets the post-schema-compilation value for all the elements in the schema.

FinalDefault

Gets or sets the finalDefault attribute which sets the default value of the final attribute on elements and complex types in the target namespace of the schema.

Groups

Gets the post-schema-compilation value of all the groups in the schema.

Id

Gets or sets the string ID.

Includes

Gets the collection of included and imported schemas.

IsCompiled

Indicates if the schema has been compiled.

Items

Gets the collection of schema elements in the schema and is used to add new element types at the schema element level.

LineNumber Inherited from XmlSchemaObject
LinePosition Inherited from XmlSchemaObject
Namespaces Inherited from XmlSchemaObject
Notations

Gets the post-schema-compilation value for all notations in the schema.

Parent Inherited from XmlSchemaObject
SchemaTypes

Gets the post-schema-compilation value of all schema types in the schema.

SourceUri Inherited from XmlSchemaObject
TargetNamespace

Gets or sets the Uniform Resource Identifier (URI) of the schema target namespace.

UnhandledAttributes

Gets and sets the qualified attributes which do not belong to the schema target namespace.

Version

Gets or sets the version of the schema.

Methods

Compile(ValidationEventHandler)

Compiles the XML Schema Object Model (SOM) into schema information for validation. Used to check the syntactic and semantic structure of the programmatically built SOM. Semantic validation checking is performed during compilation.

Compile(ValidationEventHandler, XmlResolver)

Compiles the XML Schema Object Model (SOM) into schema information for validation. Used to check the syntactic and semantic structure of the programmatically built SOM. Semantic validation checking is performed during compilation.

Equals(Object) Inherited from Object
Equals(Object, Object) Inherited from Object
GetHashCode() Inherited from Object
GetType() Inherited from Object
MemberwiseClone() Inherited from Object
Read(Stream, ValidationEventHandler)

Reads an XML Schema from the supplied stream.

Read(TextReader, ValidationEventHandler)

Reads an XML Schema from the supplied TextReader.

Read(XmlReader, ValidationEventHandler)

Reads an XML Schema from the supplied XmlReader.

ReferenceEquals(Object, Object) Inherited from Object
ToString() Inherited from Object
Write(Stream)

Writes the XML Schema to the supplied data stream.

Write(Stream, XmlNamespaceManager)

Writes the XML Schema to the supplied Stream using the XmlNamespaceManager specified.

Write(TextWriter)

Writes the XML Schema to the supplied TextWriter.

Write(TextWriter, XmlNamespaceManager)

Writes the XML Schema to the supplied TextWriter.

Write(XmlWriter)

Writes the XML Schema to the supplied XmlWriter.

Write(XmlWriter, XmlNamespaceManager)

Writes the XML Schema to the supplied XmlWriter.

Applies to