I have been trying to use the following RegEx for both c# and javascript . Its working fine for javascript but not for c# .

c# code 

```
using System.IO;
using System;
using System.Text.RegularExpressions;
class Program
{
    static void Main()
    {
        string strMacRegEx = @"/(?=.*\d)(?=.*[a-f])[\da-f]{12}/i";
        string strName = "944a0c112129";
        bool test = Regex.IsMatch(strName,strMacRegEx);
        if(test)
        {
        Console.WriteLine("Pass");
        }
        else
        {
        Console.WriteLine("Fail");  // Returns Fail  
        }

    }
}

```

Javascript code 

```
var test = /(?=.*\d)(?=.*[a-f])[\da-f]{12}/i;
alert(test .test('944A0C112129'));//Returns true

```

Can anybody please help me how to make the above regEx work for c# too . Please help me to understand what this regular expression will do . I am very new to regular expression so cant really get why this particular regex is for