XmlSchemaChoice Class

Definition

Namespace:

System.Xml.Schema

Assembly:

System.Xml.ReaderWriter.dll

Source:

XmlSchemaChoice.cs

Represents the choice element (compositor) from the XML Schema as specified by the World Wide Web Consortium (W3C). The choice allows only one of its children to appear in an instance.

public ref class XmlSchemaChoice : System::Xml::Schema::XmlSchemaGroupBase

public class XmlSchemaChoice : System.Xml.Schema.XmlSchemaGroupBase

type XmlSchemaChoice = class
    inherit XmlSchemaGroupBase

Public Class XmlSchemaChoice
Inherits XmlSchemaGroupBase

Inheritance

Object

XmlSchemaObject

XmlSchemaAnnotated

XmlSchemaParticle

XmlSchemaGroupBase

XmlSchemaChoice

Examples

The following example creates a choice element.

#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="selected"/>
        XmlSchemaElement^ xeSelected = gcnew XmlSchemaElement();
        xeSelected->Name = "selected";
        schema->Items->Add(xeSelected);

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

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

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

        // <xs:complexType name="chadState">
        XmlSchemaComplexType^ chadState = gcnew XmlSchemaComplexType();
        schema->Items->Add(chadState);
        chadState->Name = "chadState";

        // <xs:choice minOccurs="1" maxOccurs="1">
        XmlSchemaChoice^ choice = gcnew XmlSchemaChoice();
        chadState->Particle = choice;
        choice->MinOccurs = 1;
        choice->MaxOccurs = 1;

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

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

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

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

        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="selected"/>
        XmlSchemaElement xeSelected = new XmlSchemaElement();
        xeSelected.Name = "selected";
        schema.Items.Add(xeSelected);

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

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

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

        // <xs:complexType name="chadState">
        XmlSchemaComplexType chadState = new XmlSchemaComplexType();
        schema.Items.Add(chadState);
        chadState.Name = "chadState";

        // <xs:choice minOccurs="1" maxOccurs="1">
        XmlSchemaChoice choice = new XmlSchemaChoice();
        chadState.Particle = choice;
        choice.MinOccurs = 1;
        choice.MaxOccurs = 1;

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

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

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

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

        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 Strict On
Option Explicit On

Imports System.Xml
Imports System.Xml.Schema

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

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

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

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

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

        ' <xs:complexType name="chadState">
        Dim chadState As New XmlSchemaComplexType()
        schema.Items.Add(chadState)
        chadState.Name = "chadState"

        ' <xs:choice minOccurs="1" maxOccurs="1">
        Dim choice As New XmlSchemaChoice()
        chadState.Particle = choice
        choice.MinOccurs = 1
        choice.MaxOccurs = 1

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

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

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

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

        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


    Public Shared Sub ValidationCallbackOne(ByVal sender As Object, ByVal args As ValidationEventArgs)

        Console.WriteLine(args.Message)
    End Sub
End Class

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="selected"/>
    <xs:element name="unselected"/>
    <xs:element name="dimpled"/>
    <xs:element name="perforated"/>
    
    <xs:complexType name="chadState">
        <xs:choice minOccurs="1" maxOccurs="1">
            <xs:element ref="selected"/>
            <xs:element ref="unselected"/>
            <xs:element ref="dimpled"/>
            <xs:element ref="perforated"/>
        </xs:choice>
    </xs:complexType>
</xs:schema>

Constructors

XmlSchemaChoice()

Initializes a new instance of the XmlSchemaChoice class.

Properties

Annotation	Gets or sets the annotation property. (Inherited from XmlSchemaAnnotated)
Id	Gets or sets the string id. (Inherited from XmlSchemaAnnotated)
Items	Gets the collection of the elements contained with the compositor (choice): XmlSchemaElement, XmlSchemaGroupRef, XmlSchemaChoice, XmlSchemaSequence, or XmlSchemaAny.
LineNumber	Gets or sets the line number in the file to which the schema element refers. (Inherited from XmlSchemaObject)
LinePosition	Gets or sets the line position in the file to which the schema element refers. (Inherited from XmlSchemaObject)
MaxOccurs	Gets or sets the maximum number of times the particle can occur. (Inherited from XmlSchemaParticle)
MaxOccursString	Gets or sets the number as a string value. Maximum number of times the particle can occur. (Inherited from XmlSchemaParticle)
MinOccurs	Gets or sets the minimum number of times the particle can occur. (Inherited from XmlSchemaParticle)
MinOccursString	Gets or sets the number as a string value. The minimum number of times the particle can occur. (Inherited from XmlSchemaParticle)
Namespaces	Gets or sets the XmlSerializerNamespaces to use with this schema object. (Inherited from XmlSchemaObject)
Parent	Gets or sets the parent of this XmlSchemaObject. (Inherited from XmlSchemaObject)
SourceUri	Gets or sets the source location for the file that loaded the schema. (Inherited from XmlSchemaObject)
UnhandledAttributes	Gets or sets the qualified attributes that do not belong to the current schema's target namespace. (Inherited from XmlSchemaAnnotated)

Methods

Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)