CODEWITHSUNDEEP
c#regex
Zac Borders
Zac Borders

Reputation: 137

C# Regex Validating Mac Address

I am trying to validate mac addresses. In this instance there is no - or : for example a valid mac would be either:

0000000000
00-00-00-00-00-00
00:00:00:00:00:00

However I keep getting false when run against the below code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Text.RegularExpressions;

namespace parsingxml
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.Write("Give me a mac address: ");

            string input = Console.ReadLine();
            input = input.Replace(" ", "").Replace(":","").Replace("-","");

            Regex r = new Regex("^([:xdigit:]){12}$");


            if (r.IsMatch(input))
            {
                Console.Write("Valid Mac");
            }
            else
            {
                Console.Write("Invalid Mac");
            }
            Console.Read();
        }
    }
}

OUTPUT: Invalid Mac

Upvotes: 5

Views: 18713

Answers (7)

Saijayavinoth TVS
Saijayavinoth TVS

Reputation: 21

        using System.Net.NetworkInformation;
        try{
            PhysicalAddress py = PhysicalAddress.Parse("abcd");
        }catch(Exception){
            Console.WriteLine("Mac address not valid");
        }

Upvotes: 1

user12680415
user12680415

Reputation: 1

Correct Regex expression that worked for me and accept either macaddress with either all - or all : separation is :- "^[0-9a-fA-F]{2}(((:[0-9a-fA-F]{2}){5})|((-[0-9a-fA-F]{2}){5}))$"

Upvotes: 0

CASPER
CASPER

Reputation: 1

Your regex isn't good. Here you got a good one:

public const string ValidatorInvalidMacAddress = "^([0-9A-Fa-f]{2}[:-]?){5}([0-9A-Fa-f]{2})$";

Upvotes: 0

Nicholas Carey
Nicholas Carey

Reputation: 74297

I'd use a regular expression like this one, myself:

Regex rxMacAddress = new Regex( @"^[0-9a-fA-F]{2}(((:[0-9a-fA-F]{2}){5})|((:[0-9a-fA-F]{2}){5}))$") ;

6 pairs of hex digits, separator either by colons or by hyphens, but not a mixture.

Upvotes: 0

qJake
qJake

Reputation: 17139

Try this regex instead:

^(?:[0-9a-fA-F]{2}:){5}[0-9a-fA-F]{2}|(?:[0-9a-fA-F]{2}-){5}[0-9a-fA-F]{2}|(?:[0-9a-fA-F]{2}){5}[0-9a-fA-F]{2}$

Matches:

  • 12-23-34-45-56-67
  • 12:23:34:45:56:67
  • 122334455667

But not:

  • 12:34-4556-67

Edit: Your code works for me.

enter image description here

Upvotes: 5

p.s.w.g
p.s.w.g

Reputation: 149020

Seems like you could just do this:

Regex r = new Regex("^([0-9a-fA-F]{2}(?:(?:-[0-9a-fA-F]{2}){5}|(?::[0-9a-fA-F]{2}){5}|[0-9a-fA-F]{10}))$");

Or this, which is a lot simpler and would be a little more forgiving:

Regex r = new Regex("^([0-9a-fA-F]{2}(?:[:-]?[0-9a-fA-F]{2}){5})$");

Upvotes: 2

nhahtdh
nhahtdh

Reputation: 56819

.NET regex does not have support for POSIX character class. And even if it does support, you need to enclose it in [] to make it effective, i.e. [[:xdigit:]], otherwise, it will be treated as a character class with the characters :, x, d, i, g, t.

You probably want this regex instead (for the MAC address after you have cleaned up the unwanted characters):

^[a-fA-F0-9]{12}$

Note that by cleaning up the string of space, - and :, you will allow inputs as shown below to pass:

   34:   3-342-9fbc: 6:7

DEMO

Upvotes: 10

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