将 XML 文件从网站加载到 XDocument(Silverlight 和 Windows Phone 7) [英] Load an XML file from a website into XDocument (Silverlight and Windows Phone 7)

问题描述

我有一个 XML 文件，我想在 Windows Phone 7 和 Silverlight 应用程序中访问它.XML 文件位于网络服务器上，我想通过 http://www.mydomain 访问它.com/data/this_is_my_file.xml.

I have an XML file that I want to access in an Windows Phone 7 and Silverlight application. Th XML file is on a webserver, and I want to access it through http://www.mydomain.com/data/this_is_my_file.xml.

如何使用此 URL 将 XML 文件加载到 XDocument 中?

How do I use this URL to load the XML file into an XDocument?

推荐答案

您可以使用 WebClient 或 HttpWebRequest 下载(异步)并解析响应.从网络下载和解析 XML 的最简单方法之一如下 -

You can use WebClient or HttpWebRequest to download (asynchronously) and parse the response. One of the simplest approach to download and parse XML from the web is below -

public void LoadXmlItems(string xmlUrl)
{
   WebClient client = new WebClient();
   
   client.OpenReadCompleted += (sender, e) =>
   {
        if (e.Error != null)
            return;

        Stream str = e.Result;
        XDocument xdoc = XDocument.Load(str);

        // take 10 first results
        List<RssFeedItem> rssFeedItems = (from item in xdoc.Descendants("item")
                                            select new XmlItem()
                                            {
                                                Title = item.Element("title").Value,
                                                Description = item.Element("description").Value,
                                                Url = new Uri(item.Element("link").Value, UriKind.Absolute)
                                            }).ToList();
        // close
        str.Close();

        // add results to the list
        XmlItems.Clear();
        foreach (RssFeedItem item in rssFeedItems)
        {
           XmlItems.Add(item);
        }
    };
    client.OpenReadAsync(new Uri(xmlUrl, UriKind.Absolute));
}

xmlUrl 是 Web 上 XML 文件的路径.XmlItem 就是这样一个类 -

xmlUrl is the path to the XML file on the web. XmlItem is a class like so -

public class XmlItem
{
  public string Title { get; set; }
  public string Description { get; set; }
  public Uri Url { get; set; }
}

需要注意的是，如果你是在更新一个可观察的集合，你可能会遇到跨线程异常.在上面的例子中，XmlItems 是一个 List.但是，如果您希望将 XMLItem 添加到可观察集合中，请改用这段代码 -

You need to note that you may encounter cross-thread exception if you are updating an observable collection. In the above example, XmlItems is a List<XmlItem>. However, if you wish to add the XMLItem's to an observable collection, use this piece of code instead -

Dispatcher.BeginInvoke(() =>
{
  XmlItems.Clear();
  foreach (RssFeedItem item in rssFeedItems)
  {
     XmlItems.Add(item);
  }
});

另一种方法是使用 HttpWebRequest.您可以 在此处阅读此方法并使用示例中的代码.

An alternative approach is to use HttpWebRequest. You can read about this approach here and use the code in the sample.

HTH, indyfromoz

HTH, indyfromoz

这篇关于将 XML 文件从网站加载到 XDocument(Silverlight 和 Windows Phone 7)的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！