using System;

using System.Text.RegularExpressions;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        var inputString = "1 2 3";

        var values = Regex

            .Matches(inputString, @"(?<nr>\d+)")

            .OfType<Match>()

            .Select(m => m.Groups["nr"].Value)

            .ToArray();

        Console.WriteLine("Multipe numbers: " + (values.Length > 1 ? "yep" : "nope"));

        foreach (var v in values)

        {

            Console.WriteLine(v);

        }

    }

}