String Array To String Based On Any Delimiter In C#

Sample code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApplication1
{
    class Program
  {
        public static void Main(string[] args)
         {
            string[] arr = { "one", "two", "three" };
        string  delimeter ="-";
        demo obj = new demo();
        obj.joinstring(delimeter, arr);
          }
    }
    class demo
         {
            public void joinstring(string delimeter, string[] arr)
                {
                           string joinitem = string.Join(delimeter, arr);
                           Console.WriteLine(joinitem);
               }
         }
  }