W e b t u t o r i a l s

Visual Studio.NET IDE

Define C#.NET

C# Comment

C# Variables

C# Data Types

C# Escape Sequence

C# Operators

Exercise-1

Format String

Operator Precedence

C# Keywords

Constant Variable

Type Conversion

Flow Control

Exercise on Loops and Nested Loop

C# Arrays

C# Strings

User-Define Methods

Variable Scope

C# Enumerations

C# Structure

C# Exception Handling

Object Oriented Programming

C# Classes

C# Constructor & Destructor

C# Inheritance

C# Polymorphism

C# Operator Overloading

C# Interface

Abstract Classes, Abstract Methods

Sealed Classes, Methods

C# Properties

C# Indexer

C# Delegates

C# Generics

C# Collection

System.Object

Interface

Interfaces are declared in a same way as classes, but with the keyword interface. Interface can’t be instantiated as a class. Interface can’t contain any code that implements its member. A class can support multiple interface and multiple classes can support the same interface. If a class implements an interface it has to define all its members otherwise class has to be declared abstract.

    Interface IMyInterface
    {
        // interface members
    }
    

The keyword abstract and sealed is not applicable with interface. Interface inheritance is also possible like class inheritance.

    public interface IMyInterface :IMyBaseInterface, IMyBaseInterface2
    {
        // interface members
    }
    interface circle
    {
        float area(float r);
    }
    class example : circle
    {
        public float area(float r)
        {
            float a = 3.14f * r * r;
            return a;
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            example ex = new example();
            circle cir=ex;
            float f = cir.area(5.0f);
            Console.WriteLine(f);
            Console.Read();
        }
    }