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

Abstract Classes and Abstract Methods

An abstract class cannot be instantiated directly, it need to be inherited. Abstract classes may have abstract members, which have no implementation in the base class, so an implementation must be provided in the derived class.

        abstract class Building
        {
            public abstract double CalculateHeatingCost(); // abstract method
        }
        

Abstract methods are declared without definition. So it is the responsibility of the derived class to implementation an abstract method.