list to string

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
 // List of cities
 List<string> cities = new List<string>();
 cities.Add("New York");
 cities.Add("Mumbai");
 cities.Add("Berlin");
 cities.Add("Istanbul");

 // Join strings into one CSV line
 string line = string.Join(",", cities.ToArray());
 Console.WriteLine(line);
    }
}