using System;

public class Program

{

    public static void Main()

    {

        string item ="Admin#3;";

        Console.Write(ParseMultiple(item));

    }

    private static string ParseMultiple(string lookupValues)

    {

        string returnValue = string.Empty;

        if (!string.IsNullOrEmpty(lookupValues))

            {

                string[] items = lookupValues.Split("#".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);

                foreach (string item in items)

                {

                    string lookupValue = item.Replace(";", string.Empty);

                    if (IsNumeric(lookupValue) == false)

                    {

                        returnValue = returnValue + lookupValue + ",";

                    }

                }

                returnValue = returnValue.TrimEnd(",".ToCharArray());

            }

            return returnValue;

    }

    private static bool IsNumeric(string value)

    {

        int result;

        return int.TryParse(value, out result);

    }

}