New keyword and polymorphism

The new keyword will block inherited methods referring to normally overridden methods.

In this case the base method will be called

public class Parent

    {

        public void msgShow2()

        {

            MessageBox.Show(this.show2()); 

        }

       

       

        public virtual string show2()

        {

            return "parent" + this.GetType().ToString();

        }

       

        public virtual string  show()

        {

            return  "parent" + this.GetType().ToString();   

        }

    }

public class Child1 : Parent

    {

        public override string show2()

        {

            return "Child1:override" + this.GetType().ToString();

        }

       

        public override string show()

        {

            return "Child1" + this.GetType().ToString();

        }

        public void message()

        {

            MessageBox.Show("Child1"); 

        }

    }

public class Child2 : Parent

    {

        public new string show2()

        {

            return "Child1:new" + this.GetType().ToString();

        }

        public override string show()

        {

            return "Child2" + this.GetType().ToString();

        }

        public void message()

        {

            MessageBox.Show("Child2");

        }

    }

            Running the following

            Child1 c1 = new Child1();

            Child2 c2 = new Child2();

            List<Parent> l = new List<Parent>();

            l.Add(c1);

            l.Add(c2);

            foreach (Parent p in l)

            {

                p.msgShow2();

              //c1 will be derived

              //c2 will call the base

            }