XmlSchemaKeyref Classe

Referência

Definição

Namespace:: System.Xml.Schema

Assembly:: System.Xml.ReaderWriter.dll

Assembly:: System.Xml.dll

Assembly:: netstandard.dll

Importante

Algumas informações se referem a produtos de pré-lançamento que podem ser substancialmente modificados antes do lançamento. A Microsoft não oferece garantias, expressas ou implícitas, das informações aqui fornecidas.

Essa classe representa o elemento keyref do esquema XML, conforme especificado pelo W3C (World Wide Web Consortium).

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

Herança: Object

XmlSchemaObject

XmlSchemaAnnotated

XmlSchemaIdentityConstraint
XmlSchemaKeyref

Exemplos

O exemplo a seguir cria um key elemento.

#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

O arquivo XML a seguir é gerado para o exemplo de código anterior.

<?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>

Comentários

Especifica que um valor de atributo ou elemento (ou conjunto de valores) tem uma correspondência com os do elemento especificado key unique . O nome da restrição deve ser exclusivo em um esquema.

Construtores

XmlSchemaKeyref()

Inicializa uma nova instância da classe XmlSchemaKeyref.

Propriedades

Annotation	Obtém ou define a propriedade `annotation`. (Herdado de XmlSchemaAnnotated)
Fields	Obtém a coleção de campos que se aplicam como filhos do seletor de expressão XPath (XML Path Language). (Herdado de XmlSchemaIdentityConstraint)
Id	Obtém ou define a ID de cadeia de caracteres. (Herdado de XmlSchemaAnnotated)
LineNumber	Obtém ou define o número de linha no arquivo ao qual o elemento `schema` se refere. (Herdado de XmlSchemaObject)
LinePosition	Obtém ou define a posição da linha no arquivo ao qual o elemento `schema` se refere. (Herdado de XmlSchemaObject)
Name	Obtém ou define o nome da restrição de identidade. (Herdado de XmlSchemaIdentityConstraint)
Namespaces	Obtém ou define o XmlSerializerNamespaces a ser usado com esse objeto de esquema. (Herdado de XmlSchemaObject)
Parent	Obtém ou define o pai deste XmlSchemaObject. (Herdado de XmlSchemaObject)
QualifiedName	Obtém o nome qualificado da restrição de identidade, que contém o valor de pós-compilação da propriedade `QualifiedName`. (Herdado de XmlSchemaIdentityConstraint)
Refer	Obtém ou define o nome da chave à qual essa restrição se refere em outro tipo simples ou complexo.
Selector	Obtém ou define o elemento `selector` da expressão XPath. (Herdado de XmlSchemaIdentityConstraint)
SourceUri	Obtém ou define o local de origem para o arquivo que carregou o esquema. (Herdado de XmlSchemaObject)
UnhandledAttributes	Obtém ou define os atributos qualificados que não pertencem ao namespace de destino do esquema atual. (Herdado de XmlSchemaAnnotated)

Métodos

Equals(Object)	Determina se o objeto especificado é igual ao objeto atual. (Herdado de Object)
GetHashCode()	Serve como a função de hash padrão. (Herdado de Object)
GetType()	Obtém o Type da instância atual. (Herdado de Object)
MemberwiseClone()	Cria uma cópia superficial do Object atual. (Herdado de Object)
ToString()	Retorna uma cadeia de caracteres que representa o objeto atual. (Herdado de Object)

Aplica-se a