Hello, I have compilation error 1

[davidchardonnet]

Hello,

I have compilation error: Constant Expression expected

on the following code:

site.set_country(Edit1.Text);

Does somedy knows why i have this error?
the 'site' variable is an object of the following Class;

//-------------------------------------------------
type
CSite = class(CObjet)
procedure set_country(p_country:string);
private
m_country:string;
end;
//-------------------------------------------------
procedure CSite.set_country(p_country:string);
begin
m_country:=trim(p_country);
end;
//-------------------------------------------------

Thank you

David

 

[Stretchwickster]

Looks ok to me, although is the following line a typo?

CSite = class(CObjet)

Should it be:

CSite = class(CObject)

Clive

http://www.kucu.co.uk

 

[davidchardonnet]

CObjet is the parent class I defined:
Here is its definition:

type
CObjet = class
protected
request:TADOQuery;
public
...
end;

It looks OK but it does not work, Clive! I spend a lot of time on something I can't imagine it's a problem!!

 

[Stretchwickster]

Is the class declared in the same unit as the form?
Just a guess, but maybe you need to place the form name before the Edit box reference e.g.

site.set_country(Form1.Edit1.Text);

Meanwhile, I'll test the code myself! Clive

http://www.kucu.co.uk

 

[davidchardonnet]

Hey Clive,

Sorry I missed an important thing:

site is not a CSite object but a CSiteWork which is:

type CSiteWork = class(CSite)
private
public
end;

So 'site' uses the method set_country from its ancestor CSite.

 

[Stretchwickster]

I've got the following code and it compiles and runs fine. It's declared in the same unit as the form on which the Edit1 editbox is placed.

unit uSimpleExample;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ADODB;

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

  CObjet = class
  protected
    request: TADOQuery;
  end;

  CSite = class(CObjet)
    procedure set_country(p_country: string);
  private
    m_country: string;
  end;

  type CSiteWork = class(CSite)
  private
  public
  end;


var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
  site: CSiteWork;
begin
  site := CSiteWork.Create;
  site.set_country(Edit1.Text);
  MessageDlg(site.m_country, mtInformation, [mbOK], 0);
  site.Free;
end;

{ CSite }

procedure CSite.set_country(p_country: string);
begin
  m_country := trim(p_country);
end;

end.

Clive

http://www.kucu.co.uk

 

[davidchardonnet]

My fault...

Sorry it was coming from a 'case' statement.... What a shame... You helped me discover it.... Again, you deserve a star for the time you spent for me...

Thanks again clive.

 

[Stretchwickster]

I'm glad you resolved it...thanks for the star ;-) Clive

http://www.kucu.co.uk

 

[sggaunt]

In my experince 'constant expected' error is almost always due to faulty case structures. A bit late to add this but it may be a good general tip.

Steve