Inherited

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In an overridden virtual method, it is often necessary to call the parent class’ implementation of the virtual method. This can be done with the inherited reserved word. Likewise, the inherited keyword can be used to call any method of the parent class.

This case is the simplest:

pascal

Type  
  TMyClass = Class(TComponent)  
    Constructor Create(AOwner : TComponent); override;  
  end; 

Constructor TMyClass.Create(AOwner : TComponent);  
begin  
  Inherited;  
  // Do more things  
end;

Constructors and destructors case

Constructor, example 1 :

pascal

  ...
  TTest.Create;
  begin
    Inherited; // Always at the beginning of the constructors and start the constructor (code only) of the parent class
    ...
  end;

Constructor, example 2 :

pascal

  ...
  TTest.Create(...);
  begin
    Inherited Create(...); // Always at the beginning of the constructors and start the constructor (code only) of the parent class
    ...
  end;
  ...

Destructor, example 3 :

pascal

  TTest.Destroy;
  begin
    ...
    Inherited;  // Always at the end of the destructors and start the destructor (code only) of the parent class
  end;
  ...

Virtual methods override

pascal

type  
  TMyClass = class(TStrings)  
    function GetObject(Index: Integer): TObject; override;  
  end; 

function TMyClass.GetObject(Index: Integer): TObject;
begin
  // Get result from parent class method 
  Result := inherited GetObject(Index);  
  // Do something  
end;

From the Free Pascal wiki, page "Inherited", as it stood on 2022-08-06 after a change by Kai Burghardt, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's Licensing page. If you have concerns about this material, message the admin.

Revision 3, last changed by WikiArchive 2026-11-06.

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