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c#xmlfeedxmldocumentxmlreader

Reading the Stack Overflow RSS feed


I'm trying to get a list of unanswered questions from the feed, but I am having trouble reading it.

const string RECENT_QUESTIONS = "https://stackoverflow.com/feeds";

XmlTextReader reader;
XmlDocument doc;

// Load the feed in
reader = new XmlTextReader(RECENT_QUESTIONS);
//reader.MoveToContent();

// Add the feed to the document
doc = new XmlDocument();
doc.Load(reader);

// Get the <feed> element
XmlNodeList feed = doc.GetElementsByTagName("feed");

// Loop through each item under feed and add to entries
IEnumerator ienum = feed.GetEnumerator();
List<XmlNode> entries = new List<XmlNode>();
while (ienum.MoveNext())
{
    XmlNode node = (XmlNode)ienum.Current;
    if (node.Name == "entry")
    {
        entries.Add(node);
    }
}

// Send entries to the data grid control
question_list.DataSource = entries.ToArray();

I hate to post such a "please fix the code" question, but I'm really stuck. I've tried several tutorials (some giving compile errors) but to no help. I assume I'm going the right way using an XmlReader and an XmlDocument as that's been a common thing from each guide.


Solution

  • Your enumerator ienum contains only element, the <feed> element. Nothing gets added to entries since this node's name is not entry.

    I'm guessing you want to iterate over the child nodes of the <feed> element instead. Try the following:

    const string RECENT_QUESTIONS = "http://stackoverflow.com/feeds";
    
    XmlTextReader reader;
    XmlDocument doc;
    
    // Load the feed in
    reader = new XmlTextReader(RECENT_QUESTIONS);
    //reader.MoveToContent();
    
    // Add the feed to the document
    doc = new XmlDocument();
    doc.Load(reader);
    
    // Get the <feed> element.
    XmlNodeList feed = doc.GetElementsByTagName("feed");
    XmlNode feedNode = feed.Item(0);
    
    // Get the child nodes of the <feed> element.
    XmlNodeList childNodes = feedNode.ChildNodes;
    IEnumerator ienum = childNodes.GetEnumerator();
    
    List<XmlNode> entries = new List<XmlNode>();
    
    // Iterate over the child nodes.
    while (ienum.MoveNext())
    {
        XmlNode node = (XmlNode)ienum.Current;
        if (node.Name == "entry")
        {
            entries.Add(node);
        }
    }
    
    // Send entries to the data grid control
    question_list.DataSource = entries.ToArray();