using System;

using System.Globalization;

public class Program

{

    public static void Main()

    {

        var x = "123,45";

        const NumberStyles Style = NumberStyles.AllowDecimalPoint | NumberStyles.AllowLeadingWhite | NumberStyles.AllowTrailingWhite | NumberStyles.AllowLeadingSign;

        var provider = new CultureInfo("en-US");

        decimal n;

        if (decimal.TryParse(x, Style, provider, out n))

        {

            Console.WriteLine(n);

        }

        else 

        {

            Console.WriteLine("not parsed");

        }

    }

}