Showing posts with label Convert.ToString vs .toString(). Show all posts
Showing posts with label Convert.ToString vs .toString(). Show all posts

Thursday, February 26, 2015

Difference Between .ToString() and Convert.ToString()

This is a very important question which usually ask in the interviews.

Let us discuss-

Answer- This question have very simple answer that .Tostring() can’t handle the null value but Convert.ToString can.

Example 1- understand it with the help of program.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace WebApplication2
{
    public partial class Test : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
          
            Session["Name"] = null;
            string Name=Session["Name"].ToString();

          }
    }
}



Explanation- We can see in above example that there is a session which have null value, when we apply .ToString() it will throw Exception ‘object reference not set to an instance of an object’


Example 2-

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace WebApplication2
{
    public partial class Test : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
          
            Session["Name"] = null;
            string Name= Convert.ToString( Session["Name"]);

          }
    }
}

Explanation- We can see in above example that there is a session which also have null value, when we apply Convert.ToString it will not  throw Exception, it will handle it and sting ‘Name’ have  empty string.




                                                      Author- Er. Rahul Kr. Yadav