delphi中apllication的processmessage方法的必要性
Application.ProcessMessages的作用是让Application去处理消息队伍中的消息。举例说明它的用处：你有一程序，要做一循环，
You probably ought to ask in a Borland forum. But it sounds exactly like MFC's AfxPumpMessage() or .NET's Application::DoEvents(). In other words, dispatch messages while PeekMessage() returns TRUE.Hans Passant.
