How to sort list of Ip Addresses using c#

Question

I\'ve a list of IP addresses as follows

192.168.1.5
69.52.220.44
10.152.16.23
192.168.3.10
192.168.1.4
192.168.2.1

I\'m looking for such a

Answer 1

This might look as a hack, but it does exactly what you need:

var unsortedIps =
    new[]
    {
        "192.168.1.4",
        "192.168.1.5",
        "192.168.2.1",
        "10.152.16.23",
        "69.52.220.44"
    };

var sortedIps = unsortedIps
    .Select(Version.Parse)
    .OrderBy(arg => arg)
    .Select(arg => arg.ToString())
    .ToList();

Answer 2

You may find this function useful too.

public static class ExtensionMethods
{
  public static int CompareTo(this IPAddress x, IPAddress y)
  {
    var result = x.AddressFamily.CompareTo(y.AddressFamily);
    if (result != 0)
      return result;

    var xBytes = x.GetAddressBytes();
    var yBytes = y.GetAddressBytes();

    var octets = Math.Min(xBytes.Length, yBytes.Length);
    for (var i = 0; i < octets; i++)
    {
      var octetResult = xBytes[i].CompareTo(yBytes[i]);
      if (octetResult != 0)
        return octetResult;
    }
    return 0;
  }
}

Answer 3

You can convert each IP address into an integer like so ...

69.52.220.44 =>

69 * 255 * 255 * 255 +
52 * 255 * 255 +
220 * 255 +
44

Then sort by the integer representation.

Answer 4

You can use the Array.Sort function with a function we will create for comparing two IPs:

//ips is string array
Array.Sort(ips, IpCompare);

And then put this function in the code.

private static int IpCompare(string x, string y)
    {
        string ip1 = x + '.', ip2 = y + '.';
        string xSection = "", ySection = "";
        for (int i = 0; i < ip1.Length && i < ip2.Length; i++)
        {
            if (ip1[i] == '.' && ip2[i] == '.')
            {
                if (xSection != ySection)
                    return int.Parse(xSection) - int.Parse(ySection);
                xSection = ""; // Start compare the next section
                ySection = "";
            }
            else if (ip1[i] == '.') return -1; //The first section is smaller because it's length is smaller
            else if (ip2[i] == '.') return 1;
            else
            {
                xSection += ip1[i];
                ySection += ip2[i];
            }
        }
        return 0; 
        //If we would find any difference between any section it would already return something.
        //so that mean that both IPs are the same
   }