Question

So I am trying to build a range pinger which job will be to use 2 IP addresses and then compare each to calculate which addresses must be pinged.

The problem is that after whole day of thinking of how to create code which would check for range I came up with nothing, so I came here.

Example, I am having an address range from: 192.168.0.1 to: 192.168.1.1 which means I want to ping 254 IP addresses.

How to make this happend?

What I must check in my IF statements?

As of right now I have this:

public partial class PingIPRange : Form
{
    public PingIPRange()
    {
        InitializeComponent();

        txtFrom.Text = "74.125.225.20";
        txtTo.Text = "74.125.225.30";
    }

    private void btnPing_Click(object sender, EventArgs e)
    {
        //for (int i = 0; i < int.Parse(txtRepeat.Text); i++)
        //{
            CalculateRange(txtFrom.Text, txtTo.Text);
        //}
    }

    private void CalculateRange(string addressFrom, string addressTo)
    {
        int max = 10;
        int min = 0;

        int from1 = 0;
        int from2 = 0;
        int from3 = 0;
        int from4 = 0;

        int to1 = 0;
        int to2 = 0;
        int to3 = 0;
        int to4 = 0;

        var from = txtFrom.Text.Split('.');
        var to = txtTo.Text.Split('.');

        if (from.Length == 4)
        {
            from1 = int.Parse(from[0]);
            from2 = int.Parse(from[1]);
            from3 = int.Parse(from[2]);
            from4 = int.Parse(from[3]);
        }

        if (to.Length == 4)
        {
            to1 = int.Parse(to[0]);
            to2 = int.Parse(to[1]);
            to3 = int.Parse(to[2]);
            to4 = int.Parse(to[3]);
        }

        if (from1 == to1 && from2 == to2 && from3 == to3 && from4 == to4)
        {
            Ping(string.Format("{0}.{1}.{2}.{3}", from1, from2, from3, from4));
        }
        else
        {
        }


    }

    private void Ping(string address)
    {
        Ping pingSender = new Ping();
        PingOptions options = new PingOptions();
        options.DontFragment = true;
        // Create a buffer of 32 bytes of data to be transmitted.  
        string data = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
        byte[] buffer = Encoding.ASCII.GetBytes(data);
        int timeout = 120;
        try
        {
            PingReply reply = pingSender.Send(address, timeout, buffer, options) ;
            if (reply.Status == IPStatus.Success)
            {
                /*PingReply replyy = pingSender.Send(address, timeout, buffer, options);
                if (reply.Status == IPStatus.Success)
                {
                    txtDisplay.Text += "IP: " + replyy.Address.ToString() + ". "
                        + "Round Trip: " + replyy.RoundtripTime + ". "
                        + "TTL: " + replyy.Options.Ttl + ". "
                        + "Don't Fragment: " + replyy.Options.DontFragment + ". "
                        + "Buffer Size: " + replyy.Buffer.Length + ". ";
                }*/

                txtDisplay.Text += "Host " + address + " is open." + Environment.NewLine;
            }
            else
            {
                txtDisplay.Text += "Host " + address + " is closed." + Environment.NewLine;
            }
        }
        catch (Exception ex)
        {
            txtDisplay.SelectedText += Environment.NewLine + ex.Message;
        }
    }
}

Answer 1

I’d make two functions which convert an IP address to a number and vice-versa:

static uint str2ip(string ip)
{
    string[] numbers = ip.Split('.');

    uint x1 = (uint)(Convert.ToByte(numbers[0]) << 24);
    uint x2 = (uint)(Convert.ToByte(numbers[1]) << 16);
    uint x3 = (uint)(Convert.ToByte(numbers[2]) << 8);
    uint x4 = (uint)(Convert.ToByte(numbers[3]));

    return x1 + x2 + x3 + x4;
}

and

static string ip2str(uint ip)
{
    string s1 = ((ip & 0xff000000) >> 24).ToString() + "."; 
    string s2 = ((ip & 0x00ff0000) >> 16).ToString() + ".";
    string s3 = ((ip & 0x0000ff00) >> 8).ToString() + "."; 
    string s4 = (ip & 0x000000ff).ToString();

    string ip2 = s1 + s2 + s3 + s4;
    return ip2;
}

This way you can easily iterate through all the IPs. Here’s a sample program:

static void Main(string[] args)
{
    uint startIP = str2ip("250.255.255.100");
    uint endIP = str2ip("255.0.1.255");

    for(uint currentIP = startIP; currentIP <= endIP; currentIP++) {
        string thisIP = ip2str(currentIP);
        Console.WriteLine(thisIP);
    }

    Console.ReadKey();
}