Creating an interface. : interface « Class « C# / CSharp Tutorial

using System;
public interface ILog {
    int OpenLogFile(string fileName);
    int CloseLogFile();
    void LogString(string strToLog);
public class MyLog : ILog {
    public int OpenLogFile(string fileName) {
        Console.WriteLine("Opening File {0}", fileName);
        return 0;
    public int CloseLogFile() {
        Console.WriteLine("Closing log file");
        return 0;
    public void LogString(string strToLog) {
        Console.WriteLine("Logging String {0}", strToLog);
class MainClass {
    public static void Main() {
        MyLog app = new MyLog();
        app.LogString("Hello world");

7.32.2.Interface Properties
7.32.3.Creating an interface.
7.32.4.Use interface keyword to define an interface
7.32.5.Implement an interface
7.32.6.Multiple Implementation: implement two interfaces
7.32.7.Inherited interface
7.32.8.Declare an interface and implement it
7.32.9.Interfaces and Inheritance
7.32.10.Base class and interface
7.32.11.Duplicate Interface Members
7.32.12.Accessing an interface from a class.
7.32.13.Abstract Interface: how the abstract BaseClass can interface.
7.32.14.Multiple Interfaces
7.32.15.Interface Explicit Implementation