hook 手册 Windows系统是以消息处理为其控制机制，系统通过消息为窗口过程（windows procedure）传递输入。系统和应用两者都可以产生消息。对于每个输入事件，例如用户按下了键盘上的某个键、移动了鼠标、单击了一个控件上的滚动条，等等，系统都将产生一系列消息-hook Manual Windows message handling system is based on its control mechanism, system, through the message to the window procedure (windows procedure) to pass input. Both systems and applications can generate the message. For each input event, such as the user presses a key on the keyboard, move the mouse, click a control on the scroll bar, and so on, the system will produce a series of messages