What is the difference between this:

-
What is the difference between this:
IntToStr(10)
string(10)
?

Comments

  1. Nándor KissMay 14, 2013 at 5:56 AM

    IntToStr(10) -> '10'
    string(10) -> E2089 Invalid typecast

    ReplyDelete
  2. Ingo WagnerMay 14, 2013 at 5:59 AM

    Nándor Kiss string(10) works here, I am asking because I just saw it written in some code I am fixing at work. It's actually string(i + 1), but you get the point. Do you know any way it could work?

    ReplyDelete
  3. Nándor KissMay 14, 2013 at 6:03 AM

    In XE it does not work:

    var
      S: string;

    begin
      S := string(16); // <-- [DCC Error] xxx.dpr(xx): E2089 Invalid typecast
    end.

    What is the Delphi version You're using?

    ReplyDelete
  4. Nándor KissMay 14, 2013 at 6:04 AM

    Ok i got the point.... it's some hack to manuallty set the pointer of a string... bad way...

    ReplyDelete
  5. Nándor KissMay 14, 2013 at 6:05 AM

    var
      I: Integer;
      S: string;

    begin
      I := 16;
      S := string(I + 1); <- AV here
    end.

    ReplyDelete
  6. Ingo WagnerMay 14, 2013 at 6:06 AM

    Nvm, I debugged it and there is an empty try except hiding the raise, it's like this:

    try
      doSomething;
    except
    end;

    procedure doSomething;
    begin
      [code...]
      string(i+1);
      [...code]
    end;


    Great way to break things...

    ReplyDelete
  7. Stefan GlienkeMay 14, 2013 at 6:10 AM

    That reminds me of storing strings in the TComponent.Tag property....

    ReplyDelete
  8. Martin WienoldMay 14, 2013 at 6:39 AM

    Stefan Glienke  x.Tag := NativeInt(PChar('some string'))? ;)

    ReplyDelete
  9. Ingo WagnerMay 14, 2013 at 6:42 AM

    Martin Wienold Why?

    ReplyDelete
  10. Martin WienoldMay 14, 2013 at 10:38 PM

    Ingo Wagner Jr.
    That is what we (Stefan Glienke and myself) have found in our source code .. well not exactly this, but you get the idea.

    ReplyDelete

Post a Comment