C#多字符串匹配

using System;
using System.Text.RegularExpressions;

class Program
{
    static void Main(string[] args)
    {
        string input = "This is a test string.";
        string pattern = "is|test|string";

        Regex regex = new Regex(pattern);
        MatchCollection matches = regex.Matches(input);

        foreach (Match match in matches)
        {
            Console.WriteLine("Found: {0}", match.Value);
        }
    }
}