XmlNodeEventHandler Делегат

Определение

public delegate void XmlNodeEventHandler(System::Object ^ sender, XmlNodeEventArgs ^ e);

public delegate void XmlNodeEventHandler(object? sender, XmlNodeEventArgs e);

public delegate void XmlNodeEventHandler(object sender, XmlNodeEventArgs e);

type XmlNodeEventHandler = delegate of obj * XmlNodeEventArgs -> unit

Public Delegate Sub XmlNodeEventHandler(sender As Object, e As XmlNodeEventArgs)

Параметры

Примеры

В следующем примере создается XmlSerializer, добавляется обработчик событий для UnknownNode события и выполняется десериализация объекта .

private:
   void DeserializeItem( String^ filename )
   {
      XmlSerializer^ mySerializer = gcnew XmlSerializer( ObjectToDeserialize::typeid );

      // Add an instance of the delegate to the event.
      mySerializer->UnknownNode += gcnew XmlNodeEventHandler( this, &Class1::Serializer_UnknownNode );

      // A FileStream is needed to read the file to deserialize.
      FileStream^ fs = gcnew FileStream( filename,FileMode::Open );
      ObjectToDeserialize^ o = dynamic_cast<ObjectToDeserialize^>(mySerializer->Deserialize( fs ));
   }

   void Serializer_UnknownNode( Object^ sender, XmlNodeEventArgs^ e )
   {
      Console::WriteLine( "UnknownNode Name: {0}", e->Name );
      Console::WriteLine( "UnknownNode LocalName: {0}", e->LocalName );
      Console::WriteLine( "UnknownNode Namespace URI: {0}", e->NamespaceURI );
      Console::WriteLine( "UnknownNode Text: {0}", e->Text );
      Object^ o = e->ObjectBeingDeserialized;
      Console::WriteLine( "Object being deserialized {0}", o );
      XmlNodeType myNodeType = e->NodeType;
      Console::WriteLine( myNodeType );
   }

private void DeserializeItem(string filename) {
    XmlSerializer mySerializer =
        new XmlSerializer(typeof(ObjectToDeserialize));
    // Add an instance of the delegate to the event.
    mySerializer.UnknownNode += new XmlNodeEventHandler
        (Serializer_UnknownNode);
    // A FileStream is needed to read the file to deserialize.
    FileStream fs = new FileStream(filename, FileMode.Open);
    ObjectToDeserialize o = (ObjectToDeserialize)mySerializer.Deserialize(fs);
}

private void Serializer_UnknownNode
    (object sender, XmlNodeEventArgs e) {

    Console.WriteLine("UnknownNode Name: "
                      + e.Name);
    Console.WriteLine("UnknownNode LocalName: "
                      + e.LocalName);
    Console.WriteLine("UnknownNode Namespace URI: "
                      + e.NamespaceURI);
    Console.WriteLine("UnknownNode Text: "
                      + e.Text);

    object o = e.ObjectBeingDeserialized;
    Console.WriteLine("Object being deserialized "
                      + o.ToString());

    XmlNodeType myNodeType = e.NodeType;
    Console.WriteLine(myNodeType);
}

Private Sub DeserializeItem(ByVal filename As String)
    Dim mySerializer As New XmlSerializer(GetType(ObjectToDeserialize))
    ' Add an instance of the delegate to the event.
    AddHandler mySerializer.UnknownNode, AddressOf Serializer_UnknownNode
    ' A FileStream is needed to read the file to deserialize.
    Dim fs As New FileStream(filename, FileMode.Open)
    Dim o As ObjectToDeserialize = _
        CType(mySerializer.Deserialize(fs), ObjectToDeserialize)
End Sub


Private Sub Serializer_UnknownNode _
                (ByVal sender As Object, _
                 ByVal e As XmlNodeEventArgs)
    
    Console.WriteLine("UnknownNode Name: " & e.Name)
    Console.WriteLine("UnknownNode LocalName: " & e.LocalName)
    Console.WriteLine("UnknownNode Namespace URI: " & e.NamespaceURI)
    Console.WriteLine("UnknownNode Text: " & e.Text)
    
    Dim o As Object = e.ObjectBeingDeserialized
    Console.WriteLine("Object being deserialized " & o.ToString())
    
    Dim myNodeType As XmlNodeType = e.NodeType
    Console.WriteLine(myNodeType)
End Sub

Комментарии

При создании делегата XmlNodeEventHandler определяется метод, обрабатывающий событие. Чтобы связать событие с обработчиком событий, нужно добавить в событие экземпляр делегата. Обработчик событий вызывается всякий раз, когда происходит событие, если делегат не удален. Дополнительные сведения о делегатах обработчиков событий см. в разделе Обработка и вызов событий.

Событие UnknownNode возникает только при вызове Deserialize метода .

См. также раздел

• Deserialize(Stream)
• XmlSerializer