References a method to be called when a corresponding asynchronous operation completes.
Assembly: mscorlib (in mscorlib.dll)
Use an IAsyncResult parameter, which is subsequently used to obtain the results of the asynchronous operation.delegate to process the results of an asynchronous operation in a separate thread. The delegate represents a callback method that is called when the asynchronous operation completes. The callback method takes an
For more information about asynchronous programming, see Using an AsyncCallback Delegate to End an Asynchronous Operation and Using an AsyncCallback Delegate and State Object in Event-based Asynchronous Pattern (EAP).
The following code example demonstrates using asynchronous methods in the Dns class to retrieve Domain Name System (DNS) information for user-specified computers. This example creates an delegate that references the ProcessDnsInformation method. This method is called once for each asynchronous request for DNS information.
Available since 4.5
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Available since 8.1