002三大类库02_Collection

             Console.WriteLine("----三大类库02_Collection---\r\n");
             //只介绍两种常用的

            #region List<T> 线性集合 长度可变的数组
            Console.WriteLine("----List<T>----");
            //1.List<T>,T为数据类型
            List<string> list = new List<string>();
            //2.增
            list.Add("a");//->{"a"}
            list.AddRange(new string[] { "b", "c", "a", "b" });//->{"a","b","c","a","b"}
            //3.删
            list.Remove("a");//移除所匹配的第一个元素->{"b","c","a","b"}
            list.RemoveAt(0);//->{"c","a","b"}
            //4.改
            list[1] = "e";//->{"c","e","b"}
            //5.查
            Console.WriteLine(list.Contains("e"));//->true
            Console.WriteLine(list.IndexOf("e"));//->1
            //6.遍历 for/foreach
            foreach (var s in list)
            {
                Console.Write(s + "/");//->c/e/b
            }
            Console.WriteLine();
            #endregion

            #region Dictionary<TKey,TValue> 散列集合 无序 方便快速查找
            Console.WriteLine("----Dictionary<TKey,TValue>----");
            Dictionary<string, double> dic = new Dictionary<string, double>();
            //1.增
            dic.Add("电脑", 6000.00);
            dic.Add("手机", 5000.00);
            dic.Add("桌子", 200.00);
            dic.Add("凳子", 80.00);
            //2.删
            dic.Remove("电脑");
            //3.改
            dic["手机"] = 4900.00;
            //4.查
            Console.WriteLine(dic.ContainsKey("手机"));//->true
            Console.WriteLine(dic["手机"]);//->4900.00
            //5.遍历
            foreach (KeyValuePair<string, double> item in dic)
            {
                Console.WriteLine(item);
            }
            #endregion

            Console.ReadKey();