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

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);
    }
}

#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;
};

<?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>