``` Hashtable ht = new Hashtable(); //添加元素 ht.Add("id", 1); ht.Add("name", "dash"); ht.Add("age", "20"); //遍历哈希表 foreach (DictionaryEntry item in ht) { Console.WriteLine("key:{0}",item.Key); Console.WriteLine("value:{0}", item.Value); } // 获取hash元素个数 int num = ht.Count; //元素查找 ht.Contains("id"); ht.ContainsValue(1); //元素删除 ht.Remove("age"); // 删除全部元素 ht.Clear(); ```