Go Premium for a chance to win a PS4. Enter to Win

x
?
Solved

Input Validation

Posted on 1998-11-05
1
Medium Priority
?
352 Views
Last Modified: 2010-04-04
Hi

How do I validate that the contents of an edit box (input by the user) is a positive integer?

Thanks
0
Comment
Question by:cavalry
1 Comment
 
LVL 8

Accepted Solution

by:
ZifNab earned 20 total points
ID: 1345806
Hi cavalry,

3 options :

1. Use Tedit and check the entered value when exiting the editbox
2. Use MaskEdit with an editmask which only allows figures.
3. Use a special designed numeric edit (a lot freewares!)
   --> e.g. One in the freeware RxLib (http://rx.demo.ru)
     

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    MaskEdit1: TMaskEdit;
    procedure Edit1Exit(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Edit1Exit(Sender: TObject);
begin
 try
  If StrToInt(Edit1.text) < 0 then begin
   ShowMessage('not correct value');
   Edit1.Text := '0';
  end;
 except
  // Edit1.Text contains chars
   ShowMessage('fill in only an integer value');
   Edit1.Text := '0';
 end;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
 Edit1.text := '0';
 MaskEdit1.EditMask:= '00000;1;';   {or 999999;1; }
end;

end.

Regards, Zif.

0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article explains how to create forms/units independent of other forms/units object names in a delphi project. Have you ever created a form for user input in a Delphi project and then had the need to have that same form in a other Delphi proj…
Introduction Raise your hands if you were as upset with FireMonkey as I was when I discovered that there was no TListview.  I use TListView in almost all of my applications I've written, and I was not going to compromise by resorting to TStringGrid…
Exchange organizations may use the Journaling Agent of the Transport Service to archive messages going through Exchange. However, if the Transport Service is integrated with some email content management application (such as an anti-spam), the admin…
Whether it be Exchange Server Crash Issues, Dirty Shutdown Errors or Failed to mount error, Stellar Phoenix Mailbox Exchange Recovery has always got your back. With the help of its easy to understand user interface and 3 simple steps recovery proced…

772 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question