Question

我在表单上放了一个RichEdit来表示页面的一部分。＆＃39;页面的大小＆＃39;减少，以便用户可以看到整个页面来衡量输入的效果。当＆＃39;页面＆＃39;打印时，RichEdit区域将展开并在打印机页面上移动到所需位置。下面的代码很好地处理了一个轻微的（读取MASSIVE）问题。字体不缩放。

我尝试过设置Window和Viewport的起源和范围，因为我所做的阅读似乎指向了这一点。不幸的是，我没有成功。有人可以指点我正确的方向吗？

procedure TForm10.PrintNewClick(Sender: TObject);
const

 PgHeight=1170;
 PgWidth=1170*210 div 294;
var
  EdTop,EdLeft,EdWidth,EdHeight :integer;
  wPage, hPage, xPPI, yPPI, wTwips, hTwips: integer;
  pageRect, rendRect, outline: TRect;
  po: TPageOffset;
  fr: TFormatRange;
  lastOffset, currPage, pageCount: integer;
  xOffset, yOffset: integer;
  FPageOffsets: array of TPageOffset;
  TextLenEx: TGetTextLengthEx;
  firstPage: boolean;
  PrinterRatioH,PrinterRatioV, ratio:Real;
begin
  Printer.Orientation:=poPortrait;
  //get printer to 'page' ratios
  PrinterRatioH :=Printer.PageWidth/PgWidth;
  PrinterRatioV :=Printer.PageHeight/PgHeight;

  //get positions and size of richedit on screen 'page'
  //top of richedit on screen page
  EdTop:=StrToInt(EditTop.Text);
  //left of richedit on screen page
  if EditCentre.Checked then
    EdLeft:=(PgWidth-StrToInt(EditWidth.Text)) div 2
  else
    EdLeft:=StrToInt(EditLeft.Text);
  //Width of richedit on screen page
  EdWidth:=StrToInt(EditWidth.Text);
  //  Height of richedit on screen page
  EdHeight:=StrToInt(EditHeight.Text);

  //get bounding richedit rectangle on printer
  with outline do
  begin
    left:=Round(EdLeft*PrinterRatioH );
    top:=Round(EdTop*PrinterRatioV );
    Right:=Left+Round(EdWidth*PrinterRatioH);
    Bottom:=Top+Round(EdHeight*PrinterRatioV);
  end;

  //Get the size of a printed page in printer device units
  wPage := GetDeviceCaps(Printer.Handle, PHYSICALWIDTH);
  hPage := GetDeviceCaps(Printer.Handle, PHYSICALHEIGHT);
  //Next, get the device units per inch for the printer
  xPPI := GetDeviceCaps(Printer.Handle, LOGPIXELSX);
  if TwipFactor=567 then
   xPPI :=round(xPPI / 2.54 );  //change to metric base
  yPPI := GetDeviceCaps(Printer.Handle, LOGPIXELSY);
  if TwipFactor=567 then
   yPPI :=round(yPPI / 2.54 );
  //Convert the page size from device units to twips
  wTwips := MulDiv(wPage, TwipFactor, xPPI);
  hTwips := MulDiv(hPage, TwipFactor, yPPI);
  //Save the page size in twips
  with pageRect do
  begin
    Left := 0;
    Top := 0;
    Right := wTwips;
    Bottom := hTwips
  end;

  //calculate the size and position of the rendering rectangle in twips
  with rendRect do
  begin
    Left :=MulDiv(Outline.Left, TwipFactor, xPPI);
    Top := MulDiv(Outline.Top, TwipFactor, yPPI);
    Right := MulDiv(Outline.Right, TwipFactor, xPPI);
    Bottom := MulDiv(Outline.Bottom, TwipFactor, yPPI);
  end;

  //set starting offset to zero
  po.mStart := 0;
  //Define and initialize a TFormatRange structure.
  with fr do
  begin
    hdc := Printer.Handle;
    hdcTarget  := Printer.Handle;
    chrg.cpMin := po.mStart;
    chrg.cpMax := -1;
  end;
  // how much text is in the control.
  with TextLenEx do
  begin
    flags := GTL_DEFAULT;
    codepage := CP_ACP;
  end;
  lastOffset := SendMessage(TestEdit.Handle, EM_GETTEXTLENGTHEX, wParam(@TextLenEx), 0);

  //clear the formatting buffer
  SendMessage(TestEdit.Handle, EM_FORMATRANGE, 0, 0);

  SaveDC(fr.hdc);
  SetMapMode(fr.hdc, MM_ANISOTROPIC{MM_TEXT});

  SetViewportOrgEx(fr.hdc, 0, 0, nil);
  SetViewportExtEx(fr.hdc, TestEdit.Width ,testedit.Height , nil);
  //build a table of page entries,
  while ((fr.chrg.cpMin <> -1) and (fr.chrg.cpMin < lastOffset)) do
  begin
    fr.rc := rendRect;
    fr.rcPage := pageRect;
    po.mStart := fr.chrg.cpMin;
    fr.chrg.cpMin := SendMessage(TestEdit.Handle, EM_FORMATRANGE, 0, Longint(@fr));
    po.mEnd := fr.chrg.cpMin - 1;
    po.rendRect := fr.rc;
    if High(FPageOffsets) = -1 then SetLength(FPageOffsets, 1)
    else
      SetLength(FPageOffsets, Length(FPageOffsets) + 1);
    FPageOffsets[High(FPageOffsets)] := po
  end;
  pageCount := Length(FPageOffsets);

  SendMessage(TestEdit.Handle, EM_FORMATRANGE, 0, 0);
  RestoreDC(fr.hdc, - 1);
  // print.
  Printer.BeginDoc;
    fr.hdc := Printer.Handle;
    fr.hdcTarget := Printer.Handle;
    SaveDC(fr.hdc);
    SetViewportOrgEx(fr.hdc, 0, 0, nil);
    SetViewportExtEx(fr.hdc, TestEdit.Width ,testedit.Height , nil);

    firstPage := True;
    //select from page and to page
    currPage := 0;  //Print from the first page
    pageCount := 1;  //Only One page for testing REMOVE LATER!!!
    while (currPage < pageCount) do
    begin
      if firstPage then
        firstPage := False
      else
        Printer.NewPage;
      SetViewportExtEx(fr.hdc, TestEdit.Width ,testedit.Height
      , nil);
      fr.rc := FPageOffsets[currPage].rendRect;
      fr.rcPage := pageRect;
      fr.chrg.cpMin := FPageOffsets[currPage].mStart;
      fr.chrg.cpMax := FPageOffsets[currPage].mEnd;
      fr.chrg.cpMin := SendMessage(TestEdit.Handle, EM_FORMATRANGE, 1, Longint(@fr));
      Inc(currPage);
    end;
    SetViewportOrgEx(fr.hdc, 0, 0, nil);
    //draw bounding rect
    Printer.Canvas.MoveTo(outline.Left-2,outline.Top-2);
    Printer.Canvas.LineTo(outline.Right+4,outline.Top-2);
    Printer.Canvas.LineTo(outline.Right+4,outline.Bottom+4);
    Printer.Canvas.LineTo(outline.Left-2,outline.Bottom+4);
    Printer.Canvas.LineTo(outline.Left-2,outline.Top-2);

    //restore the printer's HDC settings
    RestoreDC(fr.hdc, - 1);
  Printer.EndDoc;
  // clear RichEdit control's formatting buffer
  fr.chrg.cpMin := SendMessage(TestEdit.Handle, EM_FORMATRANGE, 0, 0);
  //delete  saved page table info
  Finalize(FPageOffsets);

end;

Answer 1

我终于找到了答案（不幸的是通过反复试验而不是逻辑）。以下是我用于类似情况的代码：

id

打印richedit XE5时缩放字体

1 个答案: