How to use Freeandnil in this case?

Question

I have the following routine that destroys forgotten forms opened by the user:

...    
        for i := qtd - 1 downto 0 do
        begin
                if (Application.components[i] is TForm) then
                begin
                    TForm(Application.components[i]).Close;
                    *** AQUI A NECESSIDADE DO *** 
                    FreeAndNil(Application.components[i]);
                end;
        end;

Note that I need to finish the forms with Freeandnil but I am not able to pass the variable, because there requires a Tobject in case the Unit/Form to be released.

Answer 1

If you have nothing programmed in OnClose it is not necessary to trigger it, for this case, of course.

    for i := qtd - 1 downto 0 do
    begin
      if (Application.components[i] is TForm) then
      begin
        {Você testou se ele é um TForm, e a resposta foi positiva, então 
         teste qualquer um dos métodos a seguir}  

        TForm(Application.components[i]).Free;
        TForm(Application.components[i]).DisposeOf;
        TForm(Application.components[i]).Destroy; {citado corretamente pelo @Roberto de Campos}
        FreeAndNil(TForm(Application.components[i]));
      end;
    end;

It is worth remembering that it is not a good practice to perform this type of treatment. The correct for processing forms would be:

1 - Cria o Formulário
2 - Exibe ele
3 - Destrói ele

Delphi is Horrible in memory management, if you have allocated something and not destroyed trusting that in the destruction of the form will clean up, you are mistaken!