The variable return null all the time

Question

My program is a webcrawler. Im trying to download images from a website. In my webcrawler site i did:

try
{
    HtmlAgilityPack.HtmlDocument doc = TimeOut.getHtmlDocumentWebClient(mainUrl, false, "", 0, "", "");
    if (doc == null)
    {
        if (wccfg.downloadcontent == true)
        {
            retwebcontent.retrieveImages(mainUrl);
        }
        failed = true;
        wccfg.failedUrls++;
        failed = false;
    }

For example when doc is null the mainUrl contain:

http://members.tripod.com/~VanessaWest/bundybowman2.jpg

Now its jumping to the retrieveImages method in the other class:

namespace GatherLinks
{
    class RetrieveWebContent
    {
        HtmlAgilityPack.HtmlDocument doc;
        string imgg;
        int images;

        public RetrieveWebContent()
        {
            images = 0;
        }

        public List<string> retrieveImages(string address)
        {
            try
            {
                doc = new HtmlAgilityPack.HtmlDocument();
                System.Net.WebClient wc = new System.Net.WebClient();
                List<string> imgList = new List<string>();
                doc.Load(wc.OpenRead(address));
                HtmlNodeCollection imgs = doc.DocumentNode.SelectNodes("//img[@src]");
                if (imgs == null) return new List<string>();

                foreach (HtmlNode img in imgs)
                {
                    if (img.Attributes["src"] == null)
                        continue;
                    HtmlAttribute src = img.Attributes["src"];

                    imgList.Add(src.Value);
                    if (src.Value.StartsWith("http") || src.Value.StartsWith("https") || src.Value.StartsWith("www"))
                    {
                        images++;
                        string[] arr = src.Value.Split('/');
                        imgg = arr[arr.Length - 1];
                        //imgg = Path.GetFileName(new Uri(src.Value).LocalPath);
                        //wc.DownloadFile(src.Value, @"d:\MyImages\" + imgg);
                        wc.DownloadFile(src.Value, "d:\\MyImages\\" + Guid.NewGuid() + ".jpg");
                    }
                }

                return imgList;
            }
            catch
            {
                Logger.Write("There Was Problem Downloading The Image: " + imgg);
                return null;

            }
        }
    }
}

Now im using a breakpoint and step line by line and after doing this line:

HtmlNodeCollection imgs = doc.DocumentNode.SelectNodes("//img[@src]");

The variable imgs is null. Then on the next line that check if its null its jumping to the end and does nothing.

How can i solve it so it will be able to download the image from http://members.tripod.com/~VanessaWest/bundybowman2.jpg ?

EDIT**

public List<string> retrieveImages(string address)
        {
            try
            {
                doc = new HtmlAgilityPack.HtmlDocument();
                System.Net.WebClient wc = new System.Net.WebClient();
                List<string> imgList = new List<string>();
                doc.Load(wc.OpenRead(address));
                string t = doc.DocumentNode.InnerText;
                HtmlNodeCollection imgs = doc.DocumentNode.SelectNodes("//img//[@src]");
                if (imgs == null) return new List<string>();

                foreach (HtmlNode img in imgs)
                {
                    if (img.Attributes["src"] == null)
                        continue;
                    HtmlAttribute src = img.Attributes["src"];
                    wc.DownloadFile(src.Value, "d:\\MyImages\\" + Guid.NewGuid() + ".jpg");
                    imgList.Add(src.Value);
                    if (src.Value.StartsWith("http") || src.Value.StartsWith("https") || src.Value.StartsWith("www"))
                    {
                        images++;
                        string[] arr = src.Value.Split('/');
                        imgg = arr[arr.Length - 1];
                        //imgg = Path.GetFileName(new Uri(src.Value).LocalPath);
                        //wc.DownloadFile(src.Value, @"d:\MyImages\" + imgg);
                        wc.DownloadFile(src.Value, "d:\\MyImages\\" + Guid.NewGuid() + ".jpg");
                    }
                }

                return imgList;
            }
            catch
            {
                Logger.Write("There Was Problem Downloading The Image: " + imgg);
                return null;

            }
        }

Answer 1

If you look inside data which WebClient returns to you, you see that there is not a Html page, but bit-data of the image.

doc.Load(wc.OpenRead(address));
Console.WriteLine(doc.DocumentNode.InnerText);