using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        Coordinate coord = null;;

        string errorMessage = string.Empty;

        var success = Coordinate.TryParse("3.14, 15.28b", out coord, out errorMessage);

        if (!success) {

            Console.WriteLine("Error: " + errorMessage);

            Console.WriteLine("Coordinate is valid?: " + coord.IsValid());

        }

        else {

            Console.WriteLine("Success: " + coord.ToString());

        }

    }

    public class Coordinate {

        private Coordinate() {}

        public Coordinate(decimal x, decimal y) : this() {

            X = x;

            Y = y;

        }

        public decimal? X { get; set; }

        public decimal? Y { get; set; }

        public const char AxisSeparator = ',';

​

        public bool IsValid() {

            return X.HasValue && Y.HasValue;

        }

​

        // Try to parse a coordinate text in the format "X.XX, Y.YY"

        // If the parsing is not successful, returns false and error message as out variable

        // Else returns true and the parsed Coordinate as out variable

        public static bool TryParse(string input, out Coordinate result, out string errorMessage) {

            errorMessage = string.Empty;

            result = new Coordinate();

            var parts = input.Split(AxisSeparator);

            if (parts.Count() != 2) {

                 errorMessage = "Expected input in format 'X.XX, Y.YY' with '" + AxisSeparator + "' to separate X and Y coordinates.";

                return false;

            }

            decimal x;

            decimal y;

            if (!decimal.TryParse(parts[0], out x)) {

                errorMessage = "Expected input in format 'X.XX, Y.YY' with X.XX as number, but it was '" + parts[0] + "'.";

                return false;

            }

            if (!decimal.TryParse(parts[1], out y)) {

                errorMessage = "Expected input in format 'X.XX, Y.YY' with Y.YY as number, but it was '" + parts[1] + "'.";

                return false;

            }

            result = new Coordinate(x, y);

            return true;

        }

        public override string ToString() { return X.ToString() + AxisSeparator + " " + Y.ToString(); }

    }

}