C# Dictionary 的几种遍历方法,排序

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 = "";