using System;

public class Program

{

    public static void Main()

    {

        var value = "1:23.4";

        var result = TimeSpan.TryParseExact(value, new string[]{"c", "m:ss.F", "mm:ss.F", "M:ss.FFFFFF", "MM:ss.FFFFFF", @"m\:s\.FFFFFF", "mm:s.FFFFFF", "M:ss.FFFFFFF", "MM:s.FFFFFF" }, System.Globalization.CultureInfo.InvariantCulture, out TimeSpan ts);

        Console.WriteLine(result);

    }

}