I don't know what's wrong with my code...
This is my code:
RECT rect;
GetWindowRect(mhMainWnd, &rect);
HDC hScrDC = GetDC(mhMainWnd);
HDC hMemDC = CreateCompatibleDC(hScrDC);
PrintWindow(mhMainWnd, hMemDC, 0);
LPDIRECT3DSURFACE9 surf = NULL;
surf->GetDC(&hMemDC);
mTestTex->GetSurfaceLevel(0, &surf);
surf->ReleaseDC(hMemDC);
surf->Release();
DeleteDC(hMemDC) ;
ReleaseDC(NULL, hScrDC);
Thanks!
