internal delegate int MyDel(int x);    public class Lambda    {       private MyDel del = delegate(int x)    { return x + 1; };//匿名方法        private MyDel del2 =        (int x) => { return x + 1; };//Lambda表达式        private MyDel del3 =            (x) => { return x + 1; };//Lambda表达式        private MyDel del4 =              x =>          x + 1;   //Lambda表达式    }