Raises a user-supplied exception if an asynchronous operation failed.
Assembly: System (in System.dll)
If you have derived your own class from the AsyncCompletedEventArgs class, your read-only properties should call the method before returning the property value. If the component's asynchronous worker code assigns an exception to the Error property or sets the Cancelled property to true, the property will raise an exception if a client tries to read its value. This prevents clients from accessing properties that are potentially not valid due to a failure in the asynchronous operation.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.