Dictionary<string, int> list = new Dictionary<string, int>();             list.Add("d", 1);             //3.0以上版本            foreach (var item in list)            {                Console.WriteLine(item.Key + item.Value);            }            //KeyValuePair<T,K>            foreach (KeyValuePair<string, int> kv in list)            {                Console.WriteLine(kv.Key + kv.Value);            }            //通过键的集合取            foreach (string key in list.Keys)            {                Console.WriteLine(key + list[key]);            }            //直接取值            foreach (int val in list.Values)            {                Console.WriteLine(val);            }             //非要采用for的方法也可            List<string> test = new List<string>(list.Keys);             for (int i = 0; i < list.Count; i++)            {                Console.WriteLine(test[i] + list[test[i]]);            } 

Dictionary<string, string> dic1Asc = dic1.OrderBy(o => o.Key).ToDictionary(o => o.Key, p => p.Value);      Dictionary<string, string> dic1desc = dic1.OrderByDescending(o => o.Key).ToDictionary(o => o.Key, p => p.Value);      Dictionary<string, string> dic1Asc1        = (from d in dic1           orderby d.Key ascending           select d).ToDictionary(k => k.Key, v => v.Value);      Dictionary<string, string> dic1desc2        = (from d in dic1           orderby d.Key descending            select d).ToDictionary(k => k.Key, v => v.Value);      List<string> list = new List<string>();      list.Add("aaa");      list.Add("ddd");      list.Add("bbb");      list.Add("ccc");      list.Add("bbb");      var ascList = list.OrderBy(o => o);      var descList = list.OrderByDescending(o => o);      var ascList1 = (from l in list                      orderby l ascending                      select l).ToList();      var descList2 = (from l in list                       orderby l descending                       select l).ToList();      string str = "";