AsyncCallback Delegate

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

Namespace: System
Assembly: mscorlib (in mscorlib.dll)

public delegate void AsyncCallback (
	IAsyncResult ar
/** @delegate */
/** @attribute SerializableAttribute() */ 
/** @attribute ComVisibleAttribute(true) */ 
public delegate void AsyncCallback (
	IAsyncResult ar
JScript supports the use of delegates, but not the declaration of new ones.



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.

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0