Stringify · Software Engineering Wiki

Combines the elements of an enumerable object into a string.

Use string.Join() to combine all elements in the IEnumerable into a string, using delimiter.
Omit the second argument, delimiter, to use the default delimiter of ",".

using System.Collections.Generic;

public static partial class _30s 
{
  public static string Stringify<T>(IEnumerable<T> elements, string delimiter = ",") 
  {
    return string.Join(delimiter, elements);
  }
}

IList<string> s = new List<string> {"a", "b", "c"};
int[] n = {1, 2, 3};

_30s.Stringify(s); // "a,b,c"
_30s.Stringify(n, " "); // "1 2 3"