Question

I’m using HtmlAgilityPack.

In this function the imageNodes in the foreach count is 0

I don’t understand why the list count is 0

The website contains many images. What I want is to get a list of the images from the site and show the list in the richTextBox1 and I also want to save all the images from the site on my hard disk.

How can I fix it ?

public void GetAllImages()
{
   // Bing Image Result for Cat, First Page
   string url = "http://www.bing.com/images/search?q=cat&go=&form=QB&qs=n";

   // For speed of dev, I use a WebClient
   WebClient client = new WebClient();
   string html = client.DownloadString(url);

   // Load the Html into the agility pack
   HtmlAgilityPack.HtmlDocument doc = new HtmlAgilityPack.HtmlDocument();
   doc.LoadHtml(html);

   // Now, using LINQ to get all Images
   List<HtmlNode> imageNodes = null;
   imageNodes = (from HtmlNode node in doc.DocumentNode.SelectNodes("//img")
                 where node.Name == "img"
                    && node.Attributes["class"] != null
                    && node.Attributes["class"].Value.StartsWith("img_")
                 select node).ToList();

   foreach (HtmlNode node in imageNodes)
   {
      // Console.WriteLine(node.Attributes["src"].Value);
      richTextBox1.Text += node.Attributes["src"].Value + Environment.NewLine;
   }
}

Answer 1

As I can see the correct class of the Bing images is sg_t. You can obtain those HtmlNodes with the following Linq query:

List<HtmlNode> imageNodes = doc.DocumentNode.Descendants("img")
    .Where(n=> n.Attributes["class"] != null && n.Attributes["class"].Value == "sg_t")
    .ToList();

This list should be filled with all the img with class = 'sg_t'