Check whether data reader null or not using DBNull.Value

using System;
using System.Linq;
using System.Text;
using System.Collections;
using System.Data;
using System.Xml;
using System.IO;
using System.Diagnostics;
using System.Collections.Generic;
using System.Data.SqlClient;

namespace BlogProject
{
class Program
{
static void Main(string[] args)
{
string Value = null;
SqlDataReader rd = new SqlDataReader();
if(rd[0] == DBNull.Value)
{
Console.WriteLine("Null Value");
}
Console.ReadLine();
}
}
}