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XmlSerializer::UnknownNode Event

Occurs when the XmlSerializer encounters an XML node of unknown type during deserialization.

Namespace:  System.Xml.Serialization
Assembly:  System.Xml (in System.Xml.dll)

 event XmlNodeEventHandler^ UnknownNode {
	void add (XmlNodeEventHandler^ value);
	void remove (XmlNodeEventHandler^ value);

By default, after calling the Deserialize method, the XmlSerializer ignores XML nodes of unknown types. However, you can use this event to handle such node types.

The following example prints the type of any encountered unknown node.

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

using namespace System;
using namespace System::IO;
using namespace System::Xml;
using namespace System::Xml::Serialization;

public ref class Group

   // Only the GroupName field will be known.
   String^ GroupName;

public ref class Test
   static void main()
      Test^ t = gcnew Test;
      t->DeserializeObject( "UnknownNodes.xml" );

   void DeserializeObject( String^ filename )
      XmlSerializer^ mySerializer = gcnew XmlSerializer( Group::typeid );
      FileStream^ fs = gcnew FileStream( filename,FileMode::Open );
      mySerializer->UnknownNode += gcnew XmlNodeEventHandler( this, &Test::serializer_UnknownNode );
      Group^ myGroup = dynamic_cast<Group^>(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 );
      XmlNodeType myNodeType = e->NodeType;
      Console::WriteLine( "NodeType: {0}", myNodeType );
      Group^ myGroup = dynamic_cast<Group^>(e->ObjectBeingDeserialized);
      Console::WriteLine( "GroupName: {0}", myGroup->GroupName );

int main()

/* Paste this XML into a file named UnknownNodes:
<?xml version="1.0" encoding="utf-8"?>
<Group xmlns:xsi="" 

xmlns:xsd="" xmlns:coho = "" 


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.