你可以看看msdn的解释The DefWindowProc function calls the default window procedure to provide default processing for any window messages that an application does not process. This function ensures that every message is processed. DefWindowProc is called with the same parameters received by the window procedure.
如果你不想DefWindowProc处理一些消息,你大可以重载相应的消息映射函数,然后在里面注释到相应默认代码,或直接返回true或false即可.范不着和DefWindowProc过不去.
以下网页内有相应代码和注释.
http://community.csdn.net/Expert/topic/3313/3313733.xml?temp=.9965021
一般游戏都屏蔽了这些快捷键消息的,特别是EA的游戏最狠,连ALT+TAB和CTRL+ALT+DEL都屏蔽了。