c# - 在列表框错误中提供 YouTube

Question

我已经尝试使用此代码在列表框中插入提要，但是对于 youtube 提要它不起作用。抱歉，我对 xml 了解不多

XmlDocument RSSXml = new XmlDocument();
RSSXml.Load("http://gdata.youtube.com/feeds/api/users/google/uploads");

XmlNodeList RSSNodeList = RSSXml.SelectNodes("feed");
XmlNode RSSDesc = RSSXml.SelectSingleNode("feed");

 foreach (XmlNode RSSNode in RSSNodeList)
 {
     XmlNode RSSSubNode;
     RSSSubNode = RSSNode.SelectSingleNode("title");
     string title = RSSSubNode != null ? RSSSubNode.InnerText : "";
     RSSSubNode = RSSNode.SelectSingleNode("link");
     string link = RSSSubNode != null ? RSSSubNode.InnerText : "";
     listBox1.Items.Add(title);                   
}

相反，这是可行的

//Fetch the subscribed RSS Feed
XmlDocument RSSXml = new XmlDocument();
RSSXml.Load("mywebsite/feed/");

XmlNodeList RSSNodeList = RSSXml.SelectNodes("rss/channel/item");
XmlNode RSSDesc = RSSXml.SelectSingleNode("rss/channel/title");

foreach (XmlNode RSSNode in RSSNodeList)
{
    XmlNode RSSSubNode;
    RSSSubNode = RSSNode.SelectSingleNode("title");
    string title = RSSSubNode != null ? RSSSubNode.InnerText : "";
    RSSSubNode = RSSNode.SelectSingleNode("link");
    string link = RSSSubNode != null ? RSSSubNode.InnerText : "";                                       
    listBox1.Items.Add(title);
    listBox2.Items.Add(link); 
}

感谢您的回答

Answer 1

命名空间在选择 xml 文档中的节点时起着重要作用。您必须添加一个 namespace 管理器并明确指出您想要的元素。选择属性(用于链接)也不同于元素的内部文本。

     XmlDocument RSSXml = new XmlDocument(); 
     RSSXml.Load("http://gdata.youtube.com/feeds/api/users/google/uploads");  

    XmlNamespaceManager nsmgr = new XmlNamespaceManager(RSSXml.NameTable);
    nsmgr.AddNamespace("tns", "http://www.w3.org/2005/Atom");

    XmlNodeList RSSNodeList = RSSXml.SelectNodes("//tns:entry", nsmgr); 
    XmlNode RSSDesc = RSSXml.SelectSingleNode("tns:feed",nsmgr);   

    foreach (XmlNode RSSNode in RSSNodeList)  {      
        XmlNode RSSSubNode;      
        RSSSubNode = RSSNode.SelectSingleNode("tns:title", nsmgr);      
        string title = RSSSubNode != null ? RSSSubNode.InnerText : "";      
        RSSSubNode = RSSNode.SelectSingleNode("tns:link/@href",nsmgr);      
        string link = RSSSubNode != null ? RSSSubNode.InnerText : "";      

        Console.WriteLine("{0} {1}",title, link);
    }

参见 SelectNodes with a namespacemanager