Delphi 如何打印TPanel内容？

我有电话。在这个面板上有一个TImage子体，很少有其他带有控件的面板等。事实上，图片包含一些图表，而带有标签的其他面板是在运行时创建的，以向用户提供其他信息。

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最近有人告诉我，如果有可能把这个面板打印出来，并把它按原样印在纸上，那就太好了。有什么线索，怎么做吗？

我发现了一篇老的usenet帖子，它提供了一个解决方案，通过将面板的内容复制到位图，可以打印：

procedure TFormPrintWindows.ButtonPrintPanelClick(Sender: TObject);
  var
    Bitmap       :  TBitmap;
    FromLeft     :  INTEGER;
    FromTop      :  INTEGER;
    PrintedWidth :  INTEGER;
    PrintedHeight:  INTEGER;
begin
  Printer.BeginDoc;
  TRY
    Bitmap := TBitmap.Create;
    TRY
      Bitmap.Width  := Panel1.Width;
      Bitmap.Height := Panel1.Height;
      Bitmap.PixelFormat := pf24bit;  // avoid palettes

      // Copy the Panel area from the Form into a separate Bitmap
      Bitmap.Canvas.CopyRect(Rect(0,0, Bitmap.Width,Bitmap.Height),
                             FormPrintWindows.Canvas,
                             Rect(Panel1.Left, Panel1.Top,
                                  Panel1.Left + Panel1.Width-1,
                                  Panel1.Top  + Panel1.Height-1) );

      // Assumes 10% left, right and top margin
      // Assumes bitmap aspect ratio > ~0.75 for portrait mode
      PrintedWidth  := MulDiv(Printer.PageWidth, 80,100);  // 80%
      PrintedHeight := MulDiv(PrintedWidth, Bitmap.Height, Bitmap.Width);
      FromLeft      := MulDiv(Printer.PageWidth, 10,100);  // 10%
      FromTop       := MulDiv(Printer.PageHeight,10,100);  // 10%

      PrintBitmap(Printer.Canvas,
        Rect(FromLeft, FromTop,
             FromLeft + PrintedWidth,
             FromTop  + PrintedHeight),
        Bitmap);
    FINALLY
      Bitmap.Free
    END;
  FINALLY
    Printer.EndDoc
  END

end;

加

//Source of Code: 
//http://www.swissdelphicenter.ch/torry/showcode.php?id=744
//Which refers to a posting to borland.public.delphi.winapi by Rodney E Geraghty, 8/8/97.

procedure PrintBitmap(Canvas: TCanvas; DestRect: TRect; Bitmap: TBitmap);
var
  BitmapHeader: pBitmapInfo;
  BitmapImage: Pointer;
  HeaderSize: DWORD;
  ImageSize: DWORD;
begin
  GetDIBSizes(Bitmap.Handle, HeaderSize, ImageSize);
  GetMem(BitmapHeader, HeaderSize);
  GetMem(BitmapImage, ImageSize);
  try
    GetDIB(Bitmap.Handle, Bitmap.Palette, BitmapHeader^, BitmapImage^);
    StretchDIBits(Canvas.Handle,
      DestRect.Left, DestRect.Top,    // Destination Origin
      DestRect.Right - DestRect.Left, // Destination Width
      DestRect.Bottom - DestRect.Top, // Destination Height
      0, 0,                           // Source Origin
      Bitmap.Width, Bitmap.Height,    // Source Width & Height
      BitmapImage,
      TBitmapInfo(BitmapHeader^),
      DIB_RGB_COLORS,
      SRCCOPY)
  finally
    FreeMem(BitmapHeader);
    FreeMem(BitmapImage)
  end
end {PrintBitmap};

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Birger的代码示例中缺少PrintBitmap，当添加缺少的方法时，它可以工作 嗯

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谢谢你的补遗！对不起，我不能同时接受这两个答案，所以至少你的答案是+1！Birger，本着SO的精神，您应该编辑您的答案，并添加Robert Love答案中的函数（出于礼貌的原因），SO的目的是存储正确的答案。感谢您向我指出。我更改了答案并添加了函数。谢谢你，罗伯特！

//Source of Code: 
//http://www.swissdelphicenter.ch/torry/showcode.php?id=744
//Which refers to a posting to borland.public.delphi.winapi by Rodney E Geraghty, 8/8/97.

procedure PrintBitmap(Canvas: TCanvas; DestRect: TRect; Bitmap: TBitmap);
var
  BitmapHeader: pBitmapInfo;
  BitmapImage: Pointer;
  HeaderSize: DWORD;
  ImageSize: DWORD;
begin
  GetDIBSizes(Bitmap.Handle, HeaderSize, ImageSize);
  GetMem(BitmapHeader, HeaderSize);
  GetMem(BitmapImage, ImageSize);
  try
    GetDIB(Bitmap.Handle, Bitmap.Palette, BitmapHeader^, BitmapImage^);
    StretchDIBits(Canvas.Handle,
      DestRect.Left, DestRect.Top,    // Destination Origin
      DestRect.Right - DestRect.Left, // Destination Width
      DestRect.Bottom - DestRect.Top, // Destination Height
      0, 0,                           // Source Origin
      Bitmap.Width, Bitmap.Height,    // Source Width & Height
      BitmapImage,
      TBitmapInfo(BitmapHeader^),
      DIB_RGB_COLORS,
      SRCCOPY)
  finally
    FreeMem(BitmapHeader);
    FreeMem(BitmapImage)
  end
end {PrintBitmap};