透明背景的处理

1.建立bitmap资源
2.增加CBitmap对象在类中
3.在对话框OnPaint()中
    CDC ImageDC;
    bmpSoftVer.LoadBitmap(IDB_CN_ABOUT);
    BITMAP bm;
    bmpSoftVer.GetBitmap(&bm);
    iSoftVerWidth = bm.bmWidth;
    iSoftVerHeight = bm.bmHeight;
    ImageDC.CreateCompatibleDC(&dc);
    CBitmap *pOldImageBMP = ImageDC.SelectObject(&bmpSoftVer);
    dc.BitBlt(0, 0, m_iSoftVerWidth, m_iSoftVerHeight, &ImageDC, 0, 0, SRCCOPY);
   
    COLORREF crMask = RGB(0xFF, 0xFF, 0xFF);
    bmpBeyondLogo.LoadBitmap(IDB_CN_BEYOND);
    bmpBeyondLogo.GetBitmap(&bm);
    iBeyondLogoWidth= bm.bmWidth;
    iBeyondLogoHeight= bm.bmHeight;
    ImageDC.SelectObject(&bmpBeyondLogo);
    TransparentBlt(dc.m_hDC, 40, 230, iBeyondLogoWidth,iBeyondLogoHeight, ImageDC.m_hDC, 0, 0, iBeyondLogoWidth, iBeyondLogoHeight,crMask);    ImageDC.SelectObject(pOldImageBMP);