A frequent task when designing applications that work with TCP/IP and the internet is to lookup an IP address from a hostname. It's much easier for users to deal with the hostname than having to type in an IP address.

First you'll add the System.Net namespace to your using section:

using System.Net;

Example of code to get address from hostname:

string howtogeek = "www.howtogeek.com";
IPAddress[] addresslist = Dns.GetHostAddresses(howtogeek);

foreach (IPAddress theaddress in addresslist)
{
   Console.WriteLine(theaddress.ToString());
}

This was tested in C# 2.0.