parse string value from a URL using c#
<p>I have a string "http://site1/site2/site3". I would like to get the value of "site2" out of the string. What is the best algorythm in C# to get the value. (no regex because it needs to be fast). I also need to make sure it doesn't throw any errors (just returns null).</p>

<p>I am thinking something like this:</p>

<pre><code>        currentURL = currentURL.ToLower().Replace("http://", "");

        int idx1 = currentURL.IndexOf("/");
        int idx2 = currentURL.IndexOf("/", idx1);

        string secondlevelSite = currentURL.Substring(idx1, idx2 - idx1);
</code></pre>
