How to find client ip address instead of server ip address in asp.net c#?

Question

I used below code for getting IP address, but it is giving server IP address.

 public static string LocalIPAddress()
        {
            IPHostEntry host;
            string localIP = "";
            host = Dns.GetHostEntry(Dns.GetHostName());
            foreach (IPAddress ip in host.AddressList)
            {
                if (ip.AddressFamily == AddressFamily.InterNetwork)
                {
                    localIP = ip.ToString();
                    break;
                }
            }

        return localIP;
    }

From website "http://whatismyipaddress.com/" I found my IP address is:

203.100.79.91

But code is providing me some different IP :

172.24.0.123

How can I get user IP instead of server ?

Please suggest.

Thanks