lazarus中截取整个屏幕画面并保存为指定文件

Procedure SaveScreenShot(const aFile:string);
var
  vBMP:Graphics.TBitmap;
  vDC : HDC;
begin
  vBMP:=Graphics.TBitmap.Create;
  vDC := GetDC(0);
  vBMP.LoadFromDevice(vDC);
  vBmp.SaveToFile(aFile);
  ReleaseDC(0,vDC);
end;