main和WinMain函数到底是怎么回事，以及QT是怎么创建窗口和消息循环的，我们已经非常清楚了-The application will enter the event loop when exec() is called. exit() will not return until the event loop exits, e.g., when quit() is called.

制定简单的Windows界面，满足初学者对C++的学习需要-To develop a simple Windows interface, beginners meet the learning needs of C++