sortlist的超难度问题

Question

我有一个sortedlist对象，键值分别是1 one 2 two 3 three 现在想在1和2之间插入键值为2  two.one,使之变为1 one 2 two.one 3 two 4 three,请问如何实现。还有如果更改其中的键值？

Answer 1

 int pos=1;//定义位置
            Dictionary<int, string> sortedlist = new Dictionary<int, string>() { 
                {1,"one"},
                {2,"two"},
                {3,"three"}
            };
            Dictionary<int, string> sortedlist1 = sortedlist.Take(pos).ToDictionary(c=>c.Key,c=>c.Value);
            sortedlist1.Add(2,"two.one");
            Dictionary<int, string> sortedlist2 = sortedlist.Skip(pos).ToDictionary(c => c.Key+1, c => c.Value);
            Dictionary<int, string> resultlist = sortedlist1.Concat(sortedlist2).ToDictionary(c => c.Key, c => c.Value);
            /*
             * + [0] {[1, one]} System.Collections.Generic.KeyValuePair<int,string>
                + [1] {[2, two.one]} System.Collections.Generic.KeyValuePair<int,string>
                + [2] {[3, two]} System.Collections.Generic.KeyValuePair<int,string>
                + [3] {[4, three]} System.Collections.Generic.KeyValuePair<int,string>             */