Abstract Method

• Abstract Method resides in abstract class and it has no body.
• Abstract Method must be overridden in non-abstract child class.

Virtual Method

• Virtual Method can reside in abstract and non-abstract class.
• It is not necessary to override virtual method in derived but it can be.
• Virtual method must have body ....can be overridden by "override keyword".....

Difference b/w Abstract and virtual method:

1. In abstract method we only declare our Method we cant give the body of the method. But in virtual method we can give body to our method.
2. Abstract method is declared only in abstract class while virtual method not has this type of restriction.
3. When we override through abstract keyword than it is only declaration overridden. But when we override through Virtual keyword than it is Definition Overridden.
4. Main difference is that in Virtual method we can use our original method but in abstract Method we can not use Original method.

here I am giving example of both:

Abstract Method:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

 

namespace ConsoleApplication1

{

    class Program

    {

        static void Main(string[] args)

        {

            abc1 obj = new abc1();

           int x= obj.ss(5, 4);

           Console.WriteLine("the result is:" + x);// we cant use our orignel method.

           Console.ReadKey(); 

        }

    }

    abstract class abc

    {

    public abstract int ss(int x,int y);

    }

    class abc1 : abc

    {

        public override int ss(int x, int y)

        {

            return x + y;

        }

    }  

}

Output:

Virtual Method:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

 

namespace vrtualmethod

{

    class Program

    {

        static void Main(string[] args)

        {

            abcd obj1 = new abcd();

            int y = obj1.dd(4, 5);

            Console.WriteLine("output of orignel method=" + y);//here we can use our Orignel method.           

            bcd obj = new bcd();

           int x= obj.dd(4,5);

           Console.WriteLine("Output of Overrided mehod:"+x);

           Console.ReadKey();

        }

    }

    class abcd

    {

        public virtual int dd(int x, int y)

        {

            return x + y;

        }

    }

    class bcd : abcd

    {

        public override int dd(int x, int y)

 

        {

            return x * y;

        }              

    }

}

Output:

If this post is useful then mark it as "Accepted Answer"

An Abstract method must be override in child classes where as virtual method is not compulsory to override.
An abstract method doesn't have implementation detail where as virtual method has it.
only abstract class can haveabstract method, any class can have virtual method.


If you Need any Referrence:
http://www.dotnetfunda.com/forums/thread7477-difference-between-abstract-and-virtual-method.aspx