public class InvertibleList<T> : List<T> { public new T this[int index] { get { if (index >= 0) return base[index]; if (Count + index < 0) throw new IndexOutOfRangeException(); return this[Count + index]; } set { if (index >= 0) base[index] = value; else { if (Count + index < 0) throw new IndexOutOfRangeException(); this[Count + index] = value; } } } } |
使用方法：
InvertibleList<string> list=new InvertibleList<string> { "1", "2", "3", "4", "5", }; list[-2] = "asd"; list.ForEach(Console.WriteLine); |
