如何实现对话框中的控件窗体半透明？

[牧童吃五谷]

想让MFC对话框中某个窗体控件实现背景透明（最好是能够设置透明度），但不影响上面的文字显示，这个该怎么实现啊？
希望能够提供一个例子？
窗体控件源代码是自己编写的。
希望能够提供具体例子

[schlafenhamster]

void CTestDlg::OnPaint() { CPaintDC dc(this); // device context for painting // TODO: Add your message handler code here CRect rc; GetClientRect(rc); // maindlg's background CDC bgDC; bgDC.CreateCompatibleDC(&dc); // draw background to srcDC HBITMAP oldBg; oldBg=(HBITMAP)bgDC.SelectObject(m_hBitmap); // CDC srcDC; srcDC.CreateCompatibleDC(&dc); CBitmap srcBMP,*OldSrc; srcBMP.CreateCompatibleBitmap(&dc, rc.right, rc.bottom); //not:OldSrc=(CBitmap *)srcDC.SelectObject(srcBMP);// First-chance exception OldSrc=srcDC.SelectObject(&srcBMP); srcDC.StretchBlt(0,0,rc.Width(),rc.Height(), &bgDC,m_Dist.x,m_Dist.y,rc.Width(),rc.Height(),SRCCOPY); // prepare white blend CDC bfDC; bfDC.CreateCompatibleDC(&dc); CBitmap bfBMP, *OldBf; bfBMP.CreateCompatibleBitmap(&dc, rc.right, rc.bottom); OldBf = bfDC.SelectObject(&bfBMP); bfDC.FillSolidRect(rc, RGB(255, 255, 255)); // Blend to srcDC BLENDFUNCTION bf = { AC_SRC_OVER, 0, 255/3, 0 }; AlphaBlend(srcDC, 0, 0, rc.Width(), rc.Height(), bfDC, 0, 0, rc.Width(), rc.Height(), bf); // output to dc dc.BitBlt(0,0,rc.Width(),rc.Height(), &srcDC,0,0,SRCCOPY); // release bfDC.SelectObject(OldBf); bfDC.DeleteDC(); bfBMP.DeleteObject(); // srcDC.SelectObject(OldSrc); srcDC.DeleteDC(); srcBMP.DeleteObject(); // bgDC.SelectObject(oldBg); bgDC.DeleteDC(); // Do not call CDialog::OnPaint() for painting messages }

[zgl7903]

SetLayeredWindowAttributes Using Layered Windows