Методы интерфейсов и их вызовы...

using System;
public static class Program {
public static void Main() {
/************************* First Example *************************/
Base b = new Base();
// Calls Dispose by using b's type: "Base's Dispose"
b.Dispose();
// Calls Dispose by using b's object's type: "Base's Dispose"
((IDisposable)b).Dispose();
/************************* Second Example ************************/
Derived d = new Derived();
// Calls Dispose by using d's type: "Derived's Dispose"
d.Dispose();
// Calls Dispose by using d's object's type: "Derived's Dispose"
 
((IDisposable)d).Dispose();
/************************* Third Example *************************/
b = new Derived();
// Calls Dispose by using b's type: "Base's Dispose"
b.Dispose();
// Calls Dispose by using b's object's type: "Derived's Dispose"
((IDisposable)b).Dispose();
}
}
// This class is derived from Object and it implements IDisposable
internal class Base : IDisposable {
// This method is implicitly sealed and cannot be overridden
public void Dispose() {
Console.WriteLine("Base's Dispose");
}
}
// This class is derived from Base and it re-implements IDisposable
internal class Derived : Base, IDisposable {
// This method cannot override Base's Dispose. 'new' is used to indicate
// that this method re-implements IDisposable's Dispose method
new public void Dispose() {
Console.WriteLine("Derived's Dispose");
// NOTE: The next line shows how to call a base class's implementation (if desired)
// base.Dispose();
}
}

        interface IPrint
    {
        void Print(string str);
    }
 
    class Printer : IPrint
    {
        void IPrint.Print(string str)
        {
            Console.WriteLine("{0}", str);
        }
    }