Solved

Print TForm.Canvas as Bitmap

Posted on 2000-02-15
5
364 Views
Last Modified: 2013-12-03
I am developing a charting application.  I use the Canvas of TForm as my drawing area.  Is there a way for me to save my drawing as a bitmap file?

My current solution is to use BitBlt, but the problem with this is that when other windows popup over the Form which is being saved; they will also be included in the bitmap.  Furthermore, with BitBlt I cannot save the canvas of a Form when the form is minimized. How do I work on this?
0
Comment
Question by:newind
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
5 Comments
 
LVL 2

Accepted Solution

by:
hubdog earned 150 total points
ID: 2521916
tform.GetFormImage method can return a tbitmap

good luck
hubdog
            
0
 
LVL 2

Expert Comment

by:hubdog
ID: 2521919
tform.GetFormImage method can return a tbitmap

good luck
hubdog
            
0
 
LVL 2

Expert Comment

by:aubs
ID: 2521927
You should try using a bitmap created in memory rather than the form's canvas to draw on. Saving the bitmap is far easier too.

These needs tidying up, but should give you a better idea...

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    procedure FormMouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  Bitmap: TBitmap;
implementation

{$R *.DFM}

procedure TForm1.FormCreate(Sender: TObject);
begin
      bitmap:= TBitmap.Create;
  bitmap.Width:= Clientwidth;
  bitmap.height:= clientheight;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  bitmap.Free;
end;

procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  bitmap.Canvas.LineTo(X,Y);
  canvas.Draw(0,0,bitmap);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  bitmap.SaveToFile('c:\temp\test.bmp');
end;

end.



Aubs
0
 
LVL 1

Expert Comment

by:AttarSoftware
ID: 2522010
Does :
 
  myBmp := tBitmap.Create ;
  myBmp.Width := Form1.Width ;
  myBmp.Height := Form1.Height ;
  Form1.PaintTo( myBmp.Canvas.Handle, 0, 0 ) ;
 
work?

Good luck,

Tim.
0
 

Author Comment

by:newind
ID: 2525426
Well I say it's a great function.  It did solve my problem.

Thanks a lot hubdog!
0

Featured Post

Enroll in May's Course of the Month

May’s Course of the Month is now available! Experts Exchange’s Premium Members and Team Accounts have access to a complimentary course each month as part of their membership—an extra way to increase training and boost professional development.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Objective: - This article will help user in how to convert their numeric value become words. How to use 1. You can copy this code in your Unit as function 2. than you can perform your function by type this code The Code   (CODE) The Im…
Introduction I have seen many questions in this Delphi topic area where queries in threads are needed or suggested. I know bumped into a similar need. This article will address some of the concepts when dealing with a multithreaded delphi database…
Excel styles will make formatting consistent and let you apply and change formatting faster. In this tutorial, you'll learn how to use Excel's built-in styles, how to modify styles, and how to create your own. You'll also learn how to use your custo…
Attackers love to prey on accounts that have privileges. Reducing privileged accounts and protecting privileged accounts therefore is paramount. Users, groups, and service accounts need to be protected to help protect the entire Active Directory …

739 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question