XmlNodeEventHandler Delegate

Definition

Namespace:

System.Xml.Serialization

Assembly:

System.Xml.XmlSerializer.dll

Represents the method that handles the UnknownNode event of an XmlSerializer.

public delegate void XmlNodeEventHandler(System::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)

Parameters

sender

Object

The source of the event.

e

XmlNodeEventArgs

An XmlNodeEventArgs that contains the event data.

Examples

The following example creates an XmlSerializer, adds an event handler for the UnknownNode event, and deserializes an object.

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

Remarks

When you create an XmlNodeEventHandler delegate, you identify the method that handles the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see Handling and Raising Events.

The UnknownNode event occurs only when you call the Deserialize method.

Extension Methods

GetMethodInfo(Delegate)

Gets an object that represents the method represented by the specified delegate.

See also

• Deserialize(Stream)
• XmlSerializer