MFC 为对话框添加背景图片并以图片大小显示

CPaintDC dc(this);
CBitmap bmpBackground;
bmpBackground.LoadBitmap(IDB_BITMAP1); //IDB_BITMAP是你自己的图对应的ID
BITMAP bitmap;
bmpBackground.GetBitmap(&bitmap);
SetWindowPos(NULL,0,0,bitmap.bmWidth,bitmap.bmHeight,SWP_NOZORDER|SWP_NOMOVE);

//	CDialog::OnPaint();
CPaintDC   dc(this);
CRect   rect;
GetClientRect(&rect);
//	GetWindowRect(&rect);
CDC   dcMem;
dcMem.CreateCompatibleDC(&dc);
CBitmap   bmpBackground;
bmpBackground.LoadBitmap(IDB_BITMAP1);   //IDB_BITMAP1是背景位图对应的ID
BITMAP   bitmap;
bmpBackground.GetBitmap(&bitmap);
CBitmap   *pbmpOld=dcMem.SelectObject(&bmpBackground);
dc.StretchBlt(0,0,rect.Width(),rect.Height(),&dcMem,0,0,bitmap.bmWidth,bitmap.bmHeight,SRCCOPY);//让显示区域矩形宽高和对话框大小一致，先目的后源！