SendAsyncProc typedef Null safety

SendAsyncProc = Void Function(IntPtr, Uint32, IntPtr, IntPtr)

Application-defined callback function used with the SendMessageCallback function. The system passes the message to the callback function after passing the message to the destination window procedure. The SENDASYNCPROC type defines a pointer to this callback function. SendAsyncProc is a placeholder for the application-defined function name.

Implementation

typedef SendAsyncProc = Void Function(IntPtr, Uint32, IntPtr, IntPtr);