using System;

using System.Text.RegularExpressions;

​

public class Program

{

    public static void Main()

    {

        string test = "main(volatage1, voltage2, current)   0,017   0,77    v   100  I";

        Regex regex = new Regex(@"\d+,?\d+");

        foreach(Match match in regex.Matches(test)) {

            Console.WriteLine(match.Value);

        }

    }

}