应该用GetWindowDC,具体如下(使用的是C++ BUILDER,
改改就可以用在DELPHI上):
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HWND HandleOfDesktop;
HDC HdcOfDesktop;
HandleOfDesktop=GetDesktopWindow();
HdcOfDesktop=GetWindowDC(HandleOfDesktop);
TextOut(HdcOfDesktop,100,100,(LPCTSTR)"This is my DESKTOP",18);
ReleaseDC(HandleOfDesktop,HdcOfDesktop);
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其中GetDesktopWindow(),GetWindowDC(),TextOut()&ReleaseDC()
均为WIN API函数。