set.cs

Gibphone is CSharp Program, it can tell you how to design p2p chat.

using System;
using System.Collections.Generic;
using System.Text;

namespace GPPlugins
{
    class Set<T> : List<T>
    {
        public new void Add(T item)
        {
            if (!Contains(item))
                base.Add(item);
        }
    }
}