WM_SYSCOMMAND消息(点击窗口的系统菜单发送的消息)

从窗口系统菜单上发送该消息，实现窗口的最大化，最小化，移动，还原，移动等操作

假设在CWnd派生类中

如，关闭窗口SC_CLOSE

SendMessage(WM_SYSCOMMAND, SC_CLOSE, NULL);

最小化窗口SC_MINIMIZE

SendMessage(WM_SYSCOMMAND, SC_MINIMIZE, NULL);

窗口移动状态SC_MOVE

SendMessage(WM_SYSCOMMAND, SC_MOVE, NULL);

改变窗口状态还有其他的方法

如，更改窗口布局

WINDOWPLACEMENT lwndpl;

WINDOWPLACEMENT * lpwndpl;

lpwndpl=&lwndpl;

GetWindowPlacement(lpwndpl);

lpwndpl->showCmd=SW_SHOW;

SetWindowPlacement(lpwndpl);

客户区移动

在OnLButtonDown中添加如下代码：

PostMessage(WM_NCLBUTTONDOWN, HTCAPTION, MAKELPARAM(point.x, point.y));

FromHandle(pMsg->hwnd)->SendMessage(WM_SYSCOMMAND,SC_MOVE+1,0);

WM_SYSCOMMAND 消息使用技巧

void CMainFrame::OnSysCommand(UINT nID, LPARAM lParam)

{

TRACE(" nID = %x", nID);

if ( nID == SC_RESTORE && ::IsZoomed(m_hWnd) ) // 最大化时屏蔽"还原"

return;

if ( nID == 0x0f032 || nID == SC_MAXIMIZE) // 屏蔽双击标题栏

{

RECT rtScreen ={0};

if ( !SystemParametersInfo(SPI_GETWORKAREA, 0, &rtScreen, 0) )

return;

else

SetWindowPos(NULL, rtScreen.left, rtScreen.top,

rtScreen.right, rtScreen.bottom, 0);

return;

}

if ( nID == 0x0f012 || nID == SC_MOVE) // 屏蔽拖动标题栏 CFileException

return;

if ( nID == 0x0f032 ) // 屏蔽双击标题栏

return;

if ( nID == 0x0f006 || nID == 0x0f001 & nID == 0x0f003 & nID == 0x0f008) // 屏蔽改变大小

return;

if ( nID == ID_SYSTEM_MENU_DEFINE) // 系统关于菜单

PostMessage(WM_COMMAND, ID_APP_ABOUT, 0);

CFrameWnd::OnSysCommand(nID, lParam);