Question

Release an object that implements interfaces

Asked by: jaja2005

Hi. I defined a class that implements an interface as follow:

TmyClass = Class(TmyControl, MyInterface)
...

When the reference count goes to 0, _release frees the object.

TmyControl inherits from TComponent. What's happen if TMyControl
defines a Destructor?

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Asked On
2009-11-03 at 11:40:55ID24868492
Topics

Delphi Programming

,

Delphi Components

,

Pascal Programming Language

Participating Experts
1
Points
500
Comments
3

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Answers

 

by: MerijnBPosted on 2009-11-03 at 11:43:20ID: 25732692

The destructor will be called just as if you free it yourself.

 

by: jaja2005Posted on 2009-11-03 at 11:55:07ID: 25732838

Sorry. I wanted to write Destroy, by the way nothing change. When reference count goes to 0 destroy is called right?

 

by: MerijnBPosted on 2009-11-03 at 12:04:34ID: 25732954

See attached snippet from system.pas
Answer: yes :)

function TInterfacedObject._Release: Integer;
begin
  Result := InterlockedDecrement(FRefCount);
  if Result = 0 then
    Destroy;
end;
                                              
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