using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"(?:foo|\G(?!^))(\d+).*?(?=(\w+))\w+(?=\1\b)";
string input = @"38 ay bee ceefooh deefoo38 ee 37 ef gee38 aitch 38 eye19 jay38 kay 99 el88 em38 en 29 ou38 38 pee 12 q38 arr 999 es38ss 555";
RegexOptions options = RegexOptions.Multiline;
foreach (Match m in Regex.Matches(input, pattern, options))
{
Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index);
}
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx