XmlSchemaKeyref Class

Definition

This class represents the keyref element from XMLSchema as specified by the World Wide Web Consortium (W3C).

public ref class XmlSchemaKeyref : System::Xml::Schema::XmlSchemaIdentityConstraint
public class XmlSchemaKeyref : System.Xml.Schema.XmlSchemaIdentityConstraint
type XmlSchemaKeyref = class
    inherit XmlSchemaIdentityConstraint
Public Class XmlSchemaKeyref
Inherits XmlSchemaIdentityConstraint
Inheritance

Examples

The following example creates a key element.

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

using namespace System;
using namespace System::Collections;
using namespace System::IO;
using namespace System::Xml;
using namespace System::Xml::Xsl;
using namespace System::Xml::Schema;
public ref class XmlSchemaObjectGenerator
{
private:
    static void ValidationCallback( Object^ /*sender*/, ValidationEventArgs^ args )
    {
        if ( args->Severity == XmlSeverityType::Warning )
            Console::Write( "WARNING: " );
        else
            if ( args->Severity == XmlSeverityType::Error )
                Console::Write( "ERROR: " );

        Console::WriteLine( args->Message );
    }

    // XmlSchemaObjectGenerator
    int main()
    {
        XmlTextReader^ tr = gcnew XmlTextReader( "empty.xsd" );
        XmlSchema^ schema = XmlSchema::Read( tr, gcnew ValidationEventHandler( XmlSchemaObjectGenerator::ValidationCallback ) );
        schema->ElementFormDefault = XmlSchemaForm::Qualified;
        schema->TargetNamespace = "http://www.example.com/Report";
        {
            XmlSchemaElement^ element = gcnew XmlSchemaElement;
            element->Name = "purchaseReport";
            XmlSchemaComplexType^ element_complexType = gcnew XmlSchemaComplexType;
            XmlSchemaSequence^ element_complexType_sequence = gcnew XmlSchemaSequence;
            {
                XmlSchemaElement^ element_complexType_sequence_element = gcnew XmlSchemaElement;
                element_complexType_sequence_element->Name = "region";
                element_complexType_sequence_element->SchemaTypeName = gcnew XmlQualifiedName( "String*","http://www.w3.org/2001/XMLSchema" );
                {
                    XmlSchemaKeyref^ element_complexType_sequence_element_keyref = gcnew XmlSchemaKeyref;
                    element_complexType_sequence_element_keyref->Name = "dummy2";
                    element_complexType_sequence_element_keyref->Selector = gcnew XmlSchemaXPath;
                    element_complexType_sequence_element_keyref->Selector->XPath = "r:zip/r:part";
                    {
                        XmlSchemaXPath^ field = gcnew XmlSchemaXPath;
                        field->XPath = "@number";
                        element_complexType_sequence_element_keyref->Fields->Add( field );
                    }
                    element_complexType_sequence_element_keyref->Refer = gcnew XmlQualifiedName( "pNumKey","http://www.example.com/Report" );
                    element_complexType_sequence_element->Constraints->Add( element_complexType_sequence_element_keyref );
                }
                element_complexType_sequence->Items->Add( element_complexType_sequence_element );
            }
            element_complexType->Particle = element_complexType_sequence;
            {
                XmlSchemaAttribute^ element_complexType_attribute = gcnew XmlSchemaAttribute;
                element_complexType_attribute->Name = "periodEnding";
                element_complexType_attribute->SchemaTypeName = gcnew XmlQualifiedName( "date","http://www.w3.org/2001/XMLSchema" );
                element_complexType->Attributes->Add( element_complexType_attribute );
            }
            element->SchemaType = element_complexType;
            {
                XmlSchemaKey^ element_key = gcnew XmlSchemaKey;
                element_key->Name = "pNumKey";
                element_key->Selector = gcnew XmlSchemaXPath;
                element_key->Selector->XPath = "r:parts/r:part";
                {
                    XmlSchemaXPath^ field = gcnew XmlSchemaXPath;
                    field->XPath = "@number";
                    element_key->Fields->Add( field );
                }
                element->Constraints->Add( element_key );
            }
            schema->Items->Add( element );
        }
        schema->Write( Console::Out );

        return 0;
    } // main
};
using System;
using System.Collections;
using System.IO;
using System.Xml;
using System.Xml.Xsl;
using System.Xml.Schema;

public class XmlSchemaObjectGenerator {

    private static void ValidationCallback(object sender, ValidationEventArgs args ){

    if(args.Severity == XmlSeverityType.Warning)
        Console.Write("WARNING: ");
    else if(args.Severity == XmlSeverityType.Error)
        Console.Write("ERROR: ");

    Console.WriteLine(args.Message);
    }

    public static void Main() {

      XmlTextReader tr = new XmlTextReader("empty.xsd");
        XmlSchema schema = XmlSchema.Read(tr, new ValidationEventHandler(ValidationCallback));

            schema.ElementFormDefault = XmlSchemaForm.Qualified;

            schema.TargetNamespace = "http://www.example.com/Report";

            {

        XmlSchemaElement element = new XmlSchemaElement();
        element.Name = "purchaseReport";

        XmlSchemaComplexType element_complexType = new XmlSchemaComplexType();

        XmlSchemaSequence element_complexType_sequence = new XmlSchemaSequence();

            {

        XmlSchemaElement element_complexType_sequence_element = new XmlSchemaElement();
        element_complexType_sequence_element.Name = "region";
        element_complexType_sequence_element.SchemaTypeName =
                new XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema")
            ;

            {

        XmlSchemaKeyref element_complexType_sequence_element_keyref = new XmlSchemaKeyref();
        element_complexType_sequence_element_keyref.Name = "dummy2";
        element_complexType_sequence_element_keyref.Selector = new XmlSchemaXPath();
            element_complexType_sequence_element_keyref.Selector.XPath = "r:zip/r:part";

            {
                XmlSchemaXPath field = new XmlSchemaXPath();
                
                field.XPath = "@number";
                element_complexType_sequence_element_keyref.Fields.Add(field);
            }
        element_complexType_sequence_element_keyref.Refer =
                new XmlQualifiedName("pNumKey", "http://www.example.com/Report")
            ;
        element_complexType_sequence_element.Constraints.Add(element_complexType_sequence_element_keyref);
            }
        element_complexType_sequence.Items.Add(element_complexType_sequence_element);
            }
        element_complexType.Particle = element_complexType_sequence;

            {

        XmlSchemaAttribute element_complexType_attribute = new XmlSchemaAttribute();
        element_complexType_attribute.Name = "periodEnding";
        element_complexType_attribute.SchemaTypeName =
                new XmlQualifiedName("date", "http://www.w3.org/2001/XMLSchema")
            ;
        element_complexType.Attributes.Add(element_complexType_attribute);
            }
        element.SchemaType = element_complexType;

            {

        XmlSchemaKey element_key = new XmlSchemaKey();
        element_key.Name = "pNumKey";
        element_key.Selector = new XmlSchemaXPath();
            element_key.Selector.XPath = "r:parts/r:part";

            {
                XmlSchemaXPath field = new XmlSchemaXPath();
                
                field.XPath = "@number";
                element_key.Fields.Add(field);
            }
        element.Constraints.Add(element_key);
            }

                schema.Items.Add(element);
            }

        schema.Write(Console.Out);
    }/* Main() */
}
//XmlSchemaObjectGenerator
Imports System.Collections
Imports System.IO
Imports System.Xml
Imports System.Xml.Xsl
Imports System.Xml.Schema

Public Class XmlSchemaObjectGenerator
   
   Private Shared Sub ValidationCallback(sender As Object, args As ValidationEventArgs)
      
      If args.Severity = XmlSeverityType.Warning Then
         Console.Write("WARNING: ")
      Else
         If args.Severity = XmlSeverityType.Error Then
            Console.Write("ERROR: ")
         End If 
      End If
      Console.WriteLine(args.Message)
   End Sub
   
   
   
   Public Shared Sub Main()
      
      
      Dim tr As New XmlTextReader("empty.xsd")
      Dim schema As XmlSchema = XmlSchema.Read(tr, New ValidationEventHandler(AddressOf ValidationCallback))
      
      schema.ElementFormDefault = XmlSchemaForm.Qualified
      
      schema.TargetNamespace = "http://www.example.com/Report"
      
      If (True) Then
         
         Dim element As New XmlSchemaElement()
         element.Name = "purchaseReport"
         
         Dim element_complexType As New XmlSchemaComplexType()
         
         Dim element_complexType_sequence As New XmlSchemaSequence()
         
         If (True) Then
            
            Dim element_complexType_sequence_element As New XmlSchemaElement()
            element_complexType_sequence_element.Name = "region"
            element_complexType_sequence_element.SchemaTypeName = New XmlQualifiedName("string", "http://www.w3.org/2001/XMLSchema")
            
            If (True) Then
               
               Dim element_complexType_sequence_element_keyref As New XmlSchemaKeyref()
               element_complexType_sequence_element_keyref.Name = "dummy2"
               element_complexType_sequence_element_keyref.Selector = New XmlSchemaXPath()
               element_complexType_sequence_element_keyref.Selector.XPath = "r:zip/r:part"
               
               If (True) Then
                  Dim field As New XmlSchemaXPath()
                  
                  field.XPath = "@number"
                  element_complexType_sequence_element_keyref.Fields.Add(field)
               End If
               element_complexType_sequence_element_keyref.Refer = New XmlQualifiedName("pNumKey", "http://www.example.com/Report")
               element_complexType_sequence_element.Constraints.Add(element_complexType_sequence_element_keyref)
            End If
            element_complexType_sequence.Items.Add(element_complexType_sequence_element)
         End If
         element_complexType.Particle = element_complexType_sequence
         
         If (True) Then
            
            Dim element_complexType_attribute As New XmlSchemaAttribute()
            element_complexType_attribute.Name = "periodEnding"
            element_complexType_attribute.SchemaTypeName = New XmlQualifiedName("date", "http://www.w3.org/2001/XMLSchema")
            element_complexType.Attributes.Add(element_complexType_attribute)
         End If
         element.SchemaType = element_complexType
         
         If (True) Then
            
            Dim element_key As New XmlSchemaKey()
            element_key.Name = "pNumKey"
            element_key.Selector = New XmlSchemaXPath()
            element_key.Selector.XPath = "r:parts/r:part"
            
            If (True) Then
               Dim field As New XmlSchemaXPath()
               
               field.XPath = "@number"
               element_key.Fields.Add(field)
            End If
            element.Constraints.Add(element_key)
         End If
         
         schema.Items.Add(element)
      End If
      
      schema.Write(Console.Out)
   End Sub
End Class

' Main() 

'XmlSchemaObjectGenerator

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

<?xml version="1.0" encoding="IBM437"?>
<xs:schema xmlns:r="http://www.example.com/Report" elementFormDefault="qualified" targetNamespace="http://www.example.com/Report" xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="purchaseReport">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="region" type="xs:string">
          <xs:keyref name="dummy2" refer="r:pNumKey">
            <xs:selector xpath="r:zip/r:part" />
            <xs:field xpath="@number" />
          </xs:keyref>
        </xs:element>
      </xs:sequence>
      <xs:attribute name="periodEnding" type="xs:date" />
    </xs:complexType>
    <xs:key name="pNumKey">
      <xs:selector xpath="r:parts/r:part" />
      <xs:field xpath="@number" />
    </xs:key>
  </xs:element>
</xs:schema>

Remarks

Specifies that an attribute or element value (or set of values) has a correspondence with those of the specified key or unique element. The constraint name must be unique within a schema.

Constructors

XmlSchemaKeyref()

Initializes a new instance of the XmlSchemaKeyref class.

Properties

Annotation

Gets or sets the annotation property.

(Inherited from XmlSchemaAnnotated)
Fields

Gets the collection of fields that apply as children for the XML Path Language (XPath) expression selector.

(Inherited from XmlSchemaIdentityConstraint)
Id

Gets or sets the string id.

(Inherited from XmlSchemaAnnotated)
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)
Name

Gets or sets the name of the identity constraint.

(Inherited from XmlSchemaIdentityConstraint)
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)
QualifiedName

Gets the qualified name of the identity constraint, which holds the post-compilation value of the QualifiedName property.

(Inherited from XmlSchemaIdentityConstraint)
Refer

Gets or sets the name of the key that this constraint refers to in another simple or complex type.

Selector

Gets or sets the XPath expression selector element.

(Inherited from XmlSchemaIdentityConstraint)
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)

Applies to