C#多态

private static void SayHello()
        {
            Console.WriteLine("hello!");
        }

        private static void SayHello(string name)
        {
            Console.WriteLine(name + " say hello!");
        }

SayHello();
SayHello("mr.tian");

class Complex
        {
            public Complex()
            {
                
            }
            public Complex(int i)
            {
                Num = i;
            }
            public int Num { get; set; }

            public static Complex operator +(Complex com1, Complex com2)
            {
                Complex result = new Complex();
                result.Num = com1.Num + com2.Num;
                return result;
            }
        }

Complex test1 = new Complex(5);
Complex test2 = new Complex(10);
Complex test3 = test1 + test2;
Console.WriteLine(test3.Num);

class Human
        {
            public virtual void CleanRoom()
            {
                Console.WriteLine("Human clean room");
            }
        }

        class Man :Human
        {
            public override void CleanRoom()
            {
                Console.WriteLine("Man clean room");
            }
        }

        class Woman : Human
        {
            public override void CleanRoom()
            {
                Console.WriteLine("Woman clean room");
            }
        }

Human human1 = new Man();
            Human human2 = new Woman();
            human1.CleanRoom();
            human2.CleanRoom();