How to get ip Ranges in C#?

Question

I am a newbie .I write a program to get IP Range in C# 4.0 it works well for the small ranges but when I go for ranges like class A IP address, my program takes a lot of time .Need some help .Here is my code (its not a good approach ). Any suggestion to write in better way.?

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

namespace ipSplitt
{
    class MainClass
    {
        public static void Main(string[] args)
        {
            string[] z = new string[4];
            int t = 0;
            string ip = "3.0.0.0";

            string[] Ip = ip.Split(new char[] { '.' });

            foreach (string m in Ip)
            {
                z[t] = m;
                t++;
            } 

            int a1, b1, c1, d1 = 0;

            a1 = Convert.ToInt32(z[0]);
            b1 = Convert.ToInt32(z[1]);
            c1 = Convert.ToInt32(z[2]);
            d1 = Convert.ToInt32(z[3]);

            string[] v = new string[4];
            string ip2 = "3.255.255.255";
            int l = 0;
            string[] Ip2 = ip2.Split(new char[] { '.' });

            foreach (string m in Ip2)
            {
                v[l] = m;
                l++;
            } 

            int a2, b2, c2, d2 = 0;

            a2 = Convert.ToInt32(v[0]);
            b2 = Convert.ToInt32(v[1]);
            c2 = Convert.ToInt32(v[2]);
            d2 = Convert.ToInt32(v[3]);

            while (d2 >= d1 || c2 > c1 || b2 > b1 || a2 > a1)
            {
                if (d1 > 255)
                {
                    d1 = 1;
                    c1++;
                }

                if (c1 > 255)
                {
                    c1 = 1;
                    b1++;
                }

                if (b1 > 255)
                {
                    b1 = 1;
                    a1++;
                }

                using (StreamWriter writer = new StreamWriter("import.txt",true))
                    writer.WriteLine(a1 + "." + b1 + "." + c1 + "." + d1);

                d1++;
            }
        }
    }
}

Answer 1

but when I go for ranges like class A IP address, my program takes a lot of time

Because you're opening and closing a file handle 255^3 times. Put the using(Streamwriter ...) block around the outer while loop.

Answer 2

Take a look at the IPAddress class in the .NET framework, and the static Parse function.