求窗口最大化和最小化时，WndProc(ref Message m)中Message的值的。
谢谢
[解决办法]
SW_HIDE = 0
Hide the window.
SW_MAXIMIZE = 3
Maximize the window.
SW_MINIMIZE = 6
Minimize the window.
SW_RESTORE = 9
Restore the window (not maximized nor minimized).
SW_SHOW = 5
Show the window.
SW_SHOWMAXIMIZED = 3
Show the window maximized.
SW_SHOWMINIMIZED = 2
Show the window minimized.
SW_SHOWMINNOACTIVE = 7
Show the window minimized but do not activate it.
SW_SHOWNA = 8
Show the window in its current state but do not activate it.
SW_SHOWNOACTIVATE = 4
Show the window in its most recent size and position but do not activate it.
SW_SHOWNORMAL = 1
Show the window and activate it (as usual).
[解决办法]
最大化是3，最小化是6
[解决办法]
SC_MINIMIZE 0xf020 最小化消息值
SC_MAXIMIZE 0xf030 最大化消息值
