Printing on both sides with normal printer

[Sprek Skik]

I came into contact with the Lazarus program at the end of last year.
Through trial and error, I have been able to create my own applications.
It is a fun challenge and if I see a problem there are my old Pascal books,
the internet and now also this forum. I am still a real beginner and have very little experience
with everything. Every now and then I have a little success.
So also with the problem of printing on both sides of an A4 sheet.
For me it was a challenge to make this a success with little information.
I hope that I especially do the beginners a favor with this.

Code: Pascal  [Select][+][-]

1. const
2.   TopMargin = 400;
3.   LeftMargin = 500;
4.   BottomMargin = 500;
5.  
6. procedure TfrmPrinterSetUp.PrintOddEven;
7. var
8.   i, Line, PageCntr, Result : Integer;
9. begin
10. Printer.BeginDoc ;
11. Printer.Canvas.Font.Name := 'MS Sans Serif';
12. Printer.Canvas.Font.Size := 10;
13. Printer.Canvas.Font.Color := clBlack;
14. Line := TopMargin;
15. PageCntr := 1;
16. for i := 0 to Memo1.Lines.Count - 1 do
17. begin
18.   Line := Line + Abs(Printer.Canvas.Font.Height);
19.   if (Line >= Printer.PageHeight - BottomMargin) then
20.     begin
21.       Line := TopMargin;
22.       PageCntr := PageCntr + 1;
23.       if (PageCntr mod 2) = 1 then Printer.NewPage;
24.     end;
25.     if (PageCntr mod 2) = 1 then
26.       Printer.Canvas.TextOut(LeftMargin, Line, Memo1.Lines[i]);
27. end;
28. Printer.EndDoc;
29. lblPageCntr.Caption := IntToStr(PageCntr);
30. // Prompt user before printing even pages
31. result := MessageDlg('Even pages will be printed on the back of the paper. Switch paper now?',mtError,mbYesNo,0);
32. if result = mrYes then
33.   begin
34.     Printer.BeginDoc ;
35.     Printer.Canvas.Font.Name := 'MS Sans Serif';
36.     Printer.Canvas.Font.Size := 10;
37.     Printer.Canvas.Font.Color := clBlack;
38.     Line := TopMargin;
39.     PageCntr := 1;
40.     for i := 0 to Memo1.Lines.Count - 1 do
41.       begin
42.         Line := Line + Abs(Printer.Canvas.Font.Height);
43.         if (Line >= Printer.PageHeight - BottomMargin) then
44.           begin
45.             Line := TopMargin;
46.             PageCntr := PageCntr + 1;
47.             if (PageCntr mod 2) = 0 then Printer.NewPage;
48.           end;
49.      if (PageCntr mod 2) = 0 then
50.        Printer.Canvas.TextOut(LeftMargin, Line, Memo1.Lines[i]);
51.    end;
52.    Printer.EndDoc;
53.    lblPageCntr.Caption := IntToStr(PageCntr);
54.  end;
55. end;
56.  
57.  

[jamie]

Beware that some printers can print double sided.  If you set that up, you don't have to worry about simulating it.