Class in C# .Net

Class in C# .Net

Class: Class is nothing but a blue print or template. Classes are reference types and they get allocated on heap. It is user defined data type that used to contains different items like

·         Data Field

·         Member  Function

·         Property

·         Constructor

·         Delegates

·         Event

·         Attribute

·         De Constructor

·         Indexer

Class Theory: There are two type class theories 

·         Within Class

·         Outside of class

Rules  of Object Oriented Programming:

·         To access data field and member function of class we have to create object of class

·         Procedure  to create object of class

·         Every object  create separate memory block

·         Keyword this  is  the owners of the class

General Syntax to create a Class object:

<Class Name> <object name>=new <Class Name> ();

 For Example: Class1 c1=new Class1 ();

Or

  <Class Name> <object name>;

  <Object name>=new <Class Name> ();

       For Example: Class1 c1;

              c1=new Class1 (); 

Note: we can access public region with the help of object directly but we cannot access private region directly

Example With Class:

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

namespace ClassExample

{

public partial class Form1 : Form

{

public Form1()

{

InitializeComponent();

}

public class Class1

{

private int a, b;

public int c;

public void SetData()

{

a = 5;

b = 7;

c = 9;

}

}

private void button1_Click(object sender, EventArgs e)

{

Class1 ob1 = new Class1();

ob1.SetData();

ob1.c = 10;

//ob1.a=25  // we cannot initialized a ,because a is private member

//ob1.b=34;

}

}

}