C#3.0新特性小結(2)

c#3.0中除了自動屬性外，還添加:

• 隱含類型局部變量(Local Variable Type Inference)
• 匿名類型(Anonymous Types)
• 對象與集合初始化器(Object and Collection Initializers)

  代碼演示實例:

//測試數組
        public static void TestArray()
        {
            //測試數組
            var intArray = new[] { 120, 110, 119 };
            var strArray = new[] { "TreeyLee", "JFlyZhao", "JFlyingchen" };

            var objArray = new[] {
             //初始化對象
            new {username="馬鵬飛",userpass="AdminDoucment"},
            new {username="周靜",userpass="周界"}
           };

            //對單個變量賦值
            var seta =intArray[0];
            var setb = strArray[1];
            var setc = objArray[1].userpass;//能夠副單個屬性 也可副單個對象objArray[0]

           //打印當前數據
            Console.WriteLine("seta:" + seta + "\nsetb:" +setb+ "\nsetc:" + setc);

        }

    /// <summary>
    /// 綜合測試匿名類型
    /// </summary>
  public class TotalTestAnnoy
  {
      //定義屬性
      public string username { get; set; }
      public string userpass { get; set; }
      public int age { get; set; }

      //定義測試方法
      public static void TestMethods()
      {
          //集合初始化器
          List<TotalTestAnnoy> TotalList = new List<TotalTestAnnoy> {
           //不能直接寫new {} 集合器中只能裝TotalTestAnnoy對象，不能var類型
            new TotalTestAnnoy{username="老顧",userpass="laogu",age=21},
            new TotalTestAnnoy{username="周靜",userpass="zhoujing",age=26},
            new TotalTestAnnoy{username="陳凱",userpass="chenkai",age=21}
          };

          //定義匿名類型
          var GetTotalList = from newtotallist in TotalList
                             where newtotallist.age == 21//吧結果定義成一個新對象 只包含兩個屬性newname 和newpass
                             select new { newname = newtotallist.username, newpass = newtotallist.userpass };
          //循環打印新對象
          foreach(var getfirst in GetTotalList)
          {
              //打印新實例結果
              Console.WriteLine("定義新實例newname:"+getfirst.newname+"\nnewpass:\n"+getfirst.newpass);
          }

      }


  }