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Small / Large Printing text in D1

boabyte
boabyte asked
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Last Modified: 2012-05-04
if I use Delphi 1.0's Printers unit to print docs I find
the following problem. After one print, if I change the printer resolution and reprint the fonts on my printout go
wacko (either bigger or smaller depending on which way the
resolution was changed) Any ideas on how to fix this?
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Watch Question

Mayby Printer.Canvas.Refresh ?
Tell more how you doing the change of Resolution;

Author

Commented:
I change the Printer resolution using the standard Delphi PrintDialog component.
I can't test this because my printer have only one resolution but mayby you assing font in bad place or you made other mistake.

Try this example from Delphi Help.

procedure TForm1.Button1Click(Sender: TObject);
var
  Line: Integer;
  PrintText : TextFile;
begin
  if PrintDialog1.Execute then
  begin
    AssignPrn(PrintText);
    Rewrite(PrintText);
    {assign the current Font setting for Memo1 to the Printer object's canvas}
    Printer.Canvas.Font := Memo1.Font;
    for Line := 0 to Memo1.Lines.Count - 1 do
      Writeln(PrintText, Memo1.Lines[Line]);
    System.Close(PrintText);
  end;
end;

This is from Lloyd's Help File. I Didn't check it.

Q:  How do I print to different printer resolutions?

A:  Despite what Delphi's help says you have to change the printer object's Font.PixelsPerInch.  And for some reason, you have to set it AFTER calling an API routine that gets the printer's hDC. The following function does it.  After calling this function, you can use Font.Size to set a font size independently of the printer's resolution.

 {-------------------------------------------------------------
Sets the logical dots per inch for the printer and sets the printer axes to point RIGHT and DOWN.  Thus (0,0) is at the top left corner of the page. Returns the page size in logical coordinates.

Note:  Must be called AFTER Printer.BeginDoc.
 --------------------------------------------------------------}

function SetPrinterScale: TPoint;

var
  DeviceDpiX, DeviceDpiY : integer;
begin
  with Printer do begin
    DeviceDpiX := GetDeviceCaps(Handle, LOGPIXELSX);
    DeviceDpiY := GetDeviceCaps(Handle, LOGPIXELSY);
    SetMapMode(Handle, MM_ISOTROPIC);
    SetWindowExt(Handle, DeviceDpiX, DeviceDpiY);
    SetViewPortExt(Handle, DeviceDpiX, DeviceDpiY);
    Result := Point(PageWidth, PageHeight);
    with Canvas do begin
      DPtoLP(Handle, Result, 1); { This API call is required... }
      Font.PixelsPerInch := DeviceDpiY; { Manual setting is required to make this work. }
    end;
  end;
 end;

{ This code came from Lloyd's help file! }

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Hi ronit! What is the Lloyd's Help and where i can get this ? I hear more but know nothing about this.
Thank you very much.
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