true if the operation synchronously;
otherwise false.
Remarks
If the synchronous completion of the call is detected in the AsyncCallback delegate, it is probable that the thread that initiated the asynchronous operation is the current thread.
Requirements
Namespace: System Assembly: mscorlib (in mscorlib.dll) Assembly Versions: 1.0.5000.0, 2.0.0.0, 4.0.0.0