using System;

​

TestInterface3 t = new TestClass();

t.Method();

​

​

    public interface TestInterface1

    {

        void Method(){

​

            System.Console.WriteLine("1");

        }

    }

​

    public interface TestInterface2

    {

        void Method(){

            System.Console.WriteLine("2");

        }

    }

​

    public interface TestInterface3: TestInterface2, TestInterface1

    {

        void Method(){

            System.Console.WriteLine("3");

        }

    }

​

    public class TestClass : TestInterface3

    {

​

    }