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AsyncCallback Delegate

References the callback method to be called when the asynchronous operation is completed.

[Visual Basic]
Public Delegate Sub AsyncCallback( _
   ByVal ar As IAsyncResult _
public delegate void AsyncCallback(
   IAsyncResult ar
public __gc __delegate void AsyncCallback(
   IAsyncResult* ar

[JScript] In JScript, you can use the delegates in the .NET Framework, but you cannot define your own.

Parameters [Visual Basic, C#, C++]

The declaration of your callback method must have the same parameters as the AsyncCallback delegate declaration.

The result of the asynchronous operation.


AsyncCallback provides a way for client applications to complete an asynchronous operation. This callback delegate is supplied to the client when the asynchronous operation is initiated. The event handler referenced by AsyncCallback contains program logic to finish processing the asynchronous task for the client.

AsyncCallback uses the IAsyncResult interface to obtain the status of the asynchronous operation.


Namespace: System

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework

Assembly: Mscorlib (in Mscorlib.dll)

See Also

System Namespace | IAsyncResult | Events and Delegates