学步园

1、创建一个基于对话框的MFC EXE

2、在对话框的 OnInitDialog 函数 中，设置对话框扩展属性 为：WS_EX_LAYERED

const WS_EX_LAYERED = 0x80000;

::SetWindowLong(GetSafeHwnd(),GWL_EXSTYLE,
GetWindowLong(GetSafeHwnd(),GWL_EXSTYLE)|WS_EX_LAYERED);

3、在对话框的 OnInitDialog 函数 中，设置对话框透明

HINSTANCE hInst;

const LWA_COLORKEY = 0x00001;
const LWA_ALPHA = 0x00002;

typedef BOOL (WINAPI *FSetLayeredWindowAttributes)(HWND,COLORREF,BYTE,DWORD);
FSetLayeredWindowAttributes SetLayeredWindowAttributes;

hInst = LoadLibrary("User32.dll");

SetLayeredWindowAttributes = (FSetLayeredWindowAttributes)
   GetProcAddress(hInst,"SetLayeredWindowAttributes");

SetLayeredWindowAttributes(GetSafeHwnd(),RGB(0,0,0),150,LWA_ALPHA);

FreeLibrary(hInst);