【VC++】 实现对话框透明显示

LONG SetWindowLong( 
  HWND hWnd, 
  int nIndex, 
  LONG dwNewLong
); 

BOOL SetLayeredWindowAttributes(          HWND hwnd,
    COLORREF crKey,
    BYTE bAlpha,
    DWORD dwFlags
);

// Set WS_EX_LAYERED on this window 
SetWindowLong(GetSafeHwnd(), 
              GWL_EXSTYLE, 
              GetWindowLong(GetSafeHwnd(), GWL_EXSTYLE) | WS_EX_LAYERED);

// Make this window 70% alpha
SetLayeredWindowAttributes(GetSafeHwnd(), 0, (255 * 70) / 100, LWA_ALPHA);

这样就可以实现窗体透明显示了。。