Class constants
lazarus / 8-Other

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PX · 2007-09-21 11:01

Hello, is it possible to have constants or read-only variables in a
class?

like:

Quote
type
   TClass = class
        const hello = 'hi';
    end;


Ive been pulling my hair trying to do this... Is there a way?

Thanks!

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antonio · 2007-09-21 13:23

Couldn't you use a field?

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PX · 2007-09-21 15:04

a field?

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antonio · 2007-09-21 15:17

Code: [Select]
type
   TClass = class
    FField:string;
   public
    property MyString:string read FField;  // a readonly property
   end;
    (...)
constructor tclass.create;
begin
  // inherited Create here;
  FField := 'hi';
end;   
     (...)

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PX · 2007-09-21 15:50

ah I see thanks =)

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pinaxe · 2016-07-04 17:22

Yep it is easy.
//-------------------------------------------
tMyClass = class(TObject)
    MyInt  :integer;
  private
    const MYCONSTANT1=3;
    procedure MyProc();
  public
    const MYCONSTANT2=4;
end;
//-------------------------------------------

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User137 · 2016-07-05 01:12

Or a function guarantees to be readonly
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i type 
TClass = class  public    function MyString: string;  end;...function
TClass.MyString;begin  Result := 'hi';end;
If you add "inline" to it, it might remove all the overhead of a
function call too.