The button number that was pressed when the mouse event was fired.
当鼠标事件触发的时候，鼠标哪个按钮被按下。
Handle to the window that will receive the mouse message corresponding to the mouse event.
希望对鼠标事件做出响应、接收鼠标消息的窗体的句柄。
Handle to the window that will receive the mouse message corresponding to the mouse event.
希望对鼠标事件做出响应、接收鼠标消息的窗体的句柄。
应用推荐