html agility pack url scraping-- getting full html link
<p>Hi I am using html agility pack from the nuget packages in order to scrape a web page to get all of the urls on the page. The code is shown below. However the way it returns to me in the output the links are just extensions of the actual website but not the full url link like <a href="http://www.foo/bar/foobar.com" rel="nofollow">http://www.foo/bar/foobar.com</a>. All I will get is "/foobar". Is there a way to get the full links of the url with the code below? 
Thanks!</p>

<pre><code>static void Main(string[] args)
    {
        List&lt;string&gt; linksToVisit = ParseLinks("https://www.facebook.com");
    }

public static List&lt;string&gt; ParseLinks(string email)
    {

        WebClient webClient = new WebClient();

        byte[] data = webClient.DownloadData(email);
        string download = Encoding.ASCII.GetString(data);

        HashSet&lt;string&gt; list = new HashSet&lt;string&gt;();

        var doc = new HtmlDocument();
        doc.LoadHtml(download);
        HtmlNodeCollection nodes =    doc.DocumentNode.SelectNodes("//a[@href]");

            foreach (var n in nodes)
            {
                string href = n.Attributes["href"].Value;
                list.Add(href);
            }
        return list.ToList();
    }
</code></pre>