This function allows for the input of any IList and outputs a formatted, readable string.

ListStringExtension.cs

using System;
using System.Collections;

namespace ExtLibrary
{
    public static class ListExtensions
    {
        public static string AsString(this IList _List)
        {
            string _Buffer = "";
            for (int x = 0; x < _List.Count; x++)
            {
                _Buffer += x == _List.Count - 1 ? _List[x] : _List[x] + ", ";
            }
            return _Buffer;
        }
    }
}