How to extract a substring from a .NET RegEx?

Question

I have an XML file containing one (or more) key/value pairs. For each of these pairs I want to extract the value which is a two-byte hex value.

So the XML contains t

Answer 1

I think you want

match.Groups[1].Value

(As Dillie-O points out in the comments, it's group 1 because group 0 is always the whole match.)

Short but complete test program:

using System;
using System.Text.RegularExpressions;

class Program
{
  static void Main()
  {
    Regex regex = new Regex("LibID([a-fA-F0-9]{4})");
    Match match = regex.Match("BeforeLibIDA67AAfter");

    if (match.Success)
    {
      Console.WriteLine("Found Match for {0}", match.Value);
      Console.WriteLine("ID was {0}", match.Groups[1].Value);
    }      
  }
}

Output:

Found Match for LibIDA67A
ID was A67A