How to Clone a Delphi Form

Creating Delphi objects (forms, components, etc) dynamically, at run-time, is a "standard" coding technique for Delphi developers. Almost every Form that you want to show modally will be created dynamically, displayed to the user and freed from the memory.

Besides instantiating Delphi Forms dynamically, you can decide to create a *clone* of an existing form - by using the TMemoryStream class.

Note: when you create a new clone from an existing form, the clone's OnCreate will not execute.

Here's how:

procedure FormClone(form : TForm) ;
var
   ms : TMemoryStream;
   clone : TForm;
begin
   ms := TMemoryStream.Create;
   try
     ms.WriteComponent(form) ;
     ms.Position := 0;
     clone := TFormClass(form.ClassType).CreateNew(Application) ;
     ms.ReadComponent(clone) ;

     clone.Left := form.Left + 10;
     clone.Top := form.Top + 10;
     clone.Show;
   finally
     ms.Free;
   end;
end;

//Usage
procedure TForm1.Button1Click(Sender: TObject) ;
begin
   FormClone(Form1) ;
end;

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