Class and Object

Class:
Class is a collection of members.It contain fields, properties, methods, operators, constructors, destructors, events and indexes.
      Syntax for Class:

                       <Access modifier> class <ClassName>
                               {
                                       //Member(s)
                               }

Access Modifiers:

        Access modifiers/Access specifiers are keywords which are specifying or restricting access level or accessibility of a class or class members.
In C#.NET access modifiers are of five types

1. Public
2. Private
3. Protected
4. Internal
5. Protected internal

Object:
Object is a instance of a class.which is used to access the class members.
      Syntax for Object Creation:

         <ClassName> <object name>=new <ClassName>;

    Syntax for accessing a class member with the respective of object:

          <Object name>.<Class members>

Example program to create a class:


using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ClassExamples
{
    class Student
    {
        public int sid, smarks;
        public string sname;
        public void Sdata()
        {
            Console.WriteLine("Enter Student Details ...");
            this.sid = Convert.ToInt32(Console.ReadLine());
            this.sname = Console.ReadLine();
            this.smarks = Convert.ToInt32(Console.ReadLine());
        }
        public void Display()
        {
            Console.WriteLine("Student id : " + this.sid);
            Console.WriteLine("Student name : " + this.sname);
            Console.WriteLine("Student marks : " + this.smarks);
        }
    }
    class StudentMain
    {
        static void Main(string[] args)
        {
            Student s = new Student();
            s.Sdata();
            s.Display();
            Console.Read();
        }
    }
}