NullReferenceException

using System;
using System.IO;

namespace parserFunction
{
    public class parserclass
    {
        public string knob_name;
        public string value;
        public parserclass()
        {
            string knob_name=String.Empty;
            value = String.Empty;
        }
    }
public static class Program
{

   public static parserclass[] parser = new parserclass[1000];
        public static void Main()
        {
            string filename = @"C:\Program Files\Microsoft Visual Studio 9.0\VC\sampleData.txt";
            int i = 0;
            int size;
            size = Program.parserModule(ref parser, filename);

        } //end of main()
        public static int parserModule(ref parserclass[] parser, string FILE_NAME)
        {
            int size = 0;
            int i = 0;
            char[] delimiter = { ' ', '\n' };
            if (!File.Exists(FILE_NAME))
            {
                Console.WriteLine("{0} does not exist", FILE_NAME);
                return -1;
            }
            using (StreamReader sr = File.OpenText(FILE_NAME))
            {
                String input;
                while ((input=sr.ReadLine())!=null)
                {
                    Console.WriteLine(input);
                    string[] words=new string[7000];
                       words = input.Split(delimiter);
                    foreach (string s in words)
                    {
                        //Console.Write(s);
                        parser[i].knob_name = s;
                        Console.WriteLine(parser[i].knob_name);
                        i++;
                    }
                }
                size = i ;
             }
                for(i = 0;i<size;i++)>
                {
                    int loc = parser[i].knob_name.IndexOf(" ");
                    if(loc == -1)
                        continue;             
                    else
                    {
                  parser[i].value=parser[i].knob_name.Substring(loc+1);
              parser[i].knob_name =parser[i].knob_name.Substring(0,loc);
                        Console.Write(parser[i].knob_name);
                        Console.WriteLine(parser[i].value);
                        
                    }

                }
            return size;
        }
}

}