Question

C# -- Regular Expression -- Password Validation

Asked by: finance_teacher

Does anyone have a C# Windows Forms
"Regular Expression" EXAMPLE that can
do the following "Password" textbox
validation when users setup their account ?

 1. must be 8+ chars long
 2. must include one+ number
 3. must include one+ letter
 4. must NOT include spaces

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Asked On
2009-08-28 at 11:49:42ID24690780
Tags

C# -- Regular Expression -- Password Validation

Topics

Microsoft Visual C#.Net

,

.NET

,

C# Programming Language

Participating Experts
3
Points
500
Comments
6

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Answers

 

by: rkworldsPosted on 2009-08-28 at 12:01:14ID: 25210620

 

by: rkworldsPosted on 2009-08-28 at 12:14:20ID: 25210732

 

by: finance_teacherPosted on 2009-08-28 at 13:18:31ID: 25211240

I just now used http://www.ultrapico.com/Expresso.htm
to create the below "Regex" property.

How can I add this to my below "textBox1_Leave"
so the MessageBox displays if the format is invalid ?
--------------------------------------------------------------------------------------
        private void textBox1_Leave(object sender, EventArgs e)
        {
            if (textBox1.Text..????????)
            {
                MessageBox.Show("Invalid Format");
            }
        }
--------------------------------------------------------------------------------------
        public static Regex test1 = new Regex(
            "([a-zA-Z0-9_\\-\\.]+)@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1" +
            ",3}\\.)|(([a-zA-Z0-9\\-]+\\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})",
            RegexOptions.IgnoreCase
            | RegexOptions.CultureInvariant
            | RegexOptions.IgnorePatternWhitespace
            | RegexOptions.Compiled
        );

 

by: chrisbrayPosted on 2009-08-31 at 07:32:36ID: 25223088

Try something like the code below

Chris Bray

Match match = test1.Match(textBox1.Text.);
            
if (!match.Success)
{
    MessageBox.Show("Invalid Format");
}

                                              
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Select allOpen in new window

 

by: finance_teacherPosted on 2009-08-31 at 07:37:25ID: 31622545

Thanks, the below worked.
----------------------------------------------------
using System.Text.RegularExpressions;

namespace WindowsFormsApplication11
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void textBox1_Leave(object sender, EventArgs e)
        {
            Match match = test1.Match(textBox1.Text);
            if (!match.Success)
            {
                MessageBox.Show("Invalid Format");
            }
        }

        public static Regex test1 = new Regex(
            "([a-zA-Z0-9_\\-\\.]+)@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1" +
            ",3}\\.)|(([a-zA-Z0-9\\-]+\\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})",
            RegexOptions.IgnoreCase
            | RegexOptions.CultureInvariant
            | RegexOptions.IgnorePatternWhitespace
            | RegexOptions.Compiled
        );


    }
}

 

by: yolipPosted on 2010-05-05 at 18:33:08ID: 32649185

I've tried this rule, but none of my test password pass the match checking... what is this means?
public static Regex test1 = new Regex(
            "([a-zA-Z0-9_\\-\\.]+)@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1" +
            ",3}\\.)|(([a-zA-Z0-9\\-]+\\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})",
            RegexOptions.IgnoreCase
            | RegexOptions.CultureInvariant
            | RegexOptions.IgnorePatternWhitespace
            | RegexOptions.Compiled
        );

20120131-EE-VQP-002

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