Want to win a PS4? Go Premium and enter to win our High-Tech Treats giveaway. Enter to Win

x
?
Solved

Freeing components

Posted on 1998-03-20
3
Medium Priority
?
159 Views
Last Modified: 2010-04-06
Do I have to close free all objects created with Free
before terminating application, or all of them are
automatically free-ed?
0
Comment
Question by:bor061297
[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
3 Comments
 
LVL 2

Accepted Solution

by:
mvz121697 earned 200 total points
ID: 1360664
As a general rule:
Free all components which you are creating yourself,
with the Create-method.
So if you are dropping components on your form, don't worry about freeing, Delphi does it for you.

But if you are creating components dynamicly, you have to free them, like this:

var fm:TForm;
begin
fm:=TForm.create(Self);
try
  // stuff...
   fm.ShowModal;
finally  
  fm.Free;
end;


BTW, if you don't follow this rule for VCL-components,
they will still automaticly be freed, when the parent is destroyed. (The parent is the object you supply as a parameter in the create-method).  
You can also let the Application be the parent, like this:

fm:=TForm.Create(Application)

If you don't free this yourself, it will be freed when the application ends.


Greetings,
MvZ




0
 
LVL 4

Expert Comment

by:d003303
ID: 1360665
just a little cosmetics, the owner is passed in the Create method. Also, if the owner is freed, all owned components are freed, too. This does not depend on the parent property.
Generally, all components on a form are owned by the form. If e.g. a label resists on a panel wich resists on a form, the owner property of all two components is the form. The parent of the label though is the panel, the parent of the panel is the form. And normally all forms are owned by the application and have no parents (except MDIChild wich has the MDIForm as a parent).

Slash/d003303
0
 

Author Comment

by:bor061297
ID: 1360666
If I create a BitMap with:

Bitmap := TBitMap.Create;

is it automatically freed when application ends?
And, who owns Bitmap created in this way
0

Featured Post

What does it mean to be "Always On"?

Is your cloud always on? With an Always On cloud you won't have to worry about downtime for maintenance or software application code updates, ensuring that your bottom line isn't affected.

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…
Hello everybody This Article will show you how to validate number with TEdit control, What's the TEdit control? TEdit is a standard Windows edit control on a form, it allows to user to write, read and copy/paste single line of text. Usua…
In this video, Percona Solutions Engineer Barrett Chambers discusses some of the basic syntax differences between MySQL and MongoDB. To learn more check out our webinar on MongoDB administration for MySQL DBA: https://www.percona.com/resources/we…
How to fix incompatible JVM issue while installing Eclipse While installing Eclipse in windows, got one error like above and unable to proceed with the installation. This video describes how to successfully install Eclipse. How to solve incompa…
Suggested Courses

609 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