擷取畫面並存成BMP及JPG檔案

uses Windows, Graphics, Jpeg;

procedure TForm1.Button1Click(Sender: TObject);
var
  dc:hdc;
  MyCanvas:TCanVas;
  Bmp:TBitmap;
  Jpg: TJpegImage;
begin
  application.Minimize; //視窗最小化
  application.ProcessMessages; //視窗取得控制
  //可能要delay一下，不然抓到空白東東
  Jpg := TJpegImage.Create;
  MyCanvas:=TCanvas.Create;
  Bmp:=tbitmap.Create;
  dc:=getdc(0);
  try
    MyCanvas.Handle := DC;

    Bmp.Width := Width;
    Bmp.Height := Height;
    Bmp.Canvas.CopyRect(Rect(0,0,Screen.Width,Screen.Height),MyCanvas,Rect    (0,0,Screen.Width,Screen.Height));
    Image1.Picture.Bitmap.Assign(Bmp);
    Bmp.SaveToFile('test.Bmp');

    Jpg.Assign(Bmp);
    Jpg.Performance:=jpBestQuality;
    Jpg.CompressionQuality := 30; //你想要的壓縮品質
    Jpg.Compress;     
    Jpg.SaveToFile('test.jpg');   
  finally     
    releasedc(0,dc);     
    MyCanvas.Free;     
    Bmp.Free;   
  end;   
  application.Restore; //視窗回復 
end;