使用 WebClient/HttpWebRequest 从 https 检索 XML - WP7

Question

我正在尝试从服务器检索 XML 文档并将其作为字符串存储在本地。在桌面 .Net 中我不需要，我只是这样做了：

        string xmlFilePath = "https://myip/";
        XDocument xDoc = XDocument.Load(xmlFilePath);

但是在 WP7 上返回：

Cannot open 'serveraddress'. The Uri parameter must be a relative path pointing to content inside the Silverlight application's XAP package. If you need to load content from an arbitrary Uri, please see the documentation on Loading XML content using WebClient/HttpWebRequest.

所以我开始使用来自here 的 WebClient/HttpWebRequest 示例，但现在它返回了：

The remote server returned an error: NotFound.

是不是因为 XML 是 https 路径？还是因为我的路径没有以 .XML 结尾？我怎么知道？感谢您的帮助。

代码如下：

    public partial class MainPage : PhoneApplicationPage
{
    WebClient client = new WebClient();
    string baseUri = "https://myip:myport/service";
    public MainPage()
    {
        InitializeComponent();
        client.DownloadStringCompleted +=
            new DownloadStringCompletedEventHandler(
            client_DownloadStringCompleted);
    }

    private void Button1_Click(object sender, RoutedEventArgs e)
    {
        client.DownloadStringAsync
          (new Uri(baseUri));
    }

    void client_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
    {
        if (e.Error == null)
            resultBlock.Text = "Using WebClient: " + e.Result;

        else
            resultBlock.Text = e.Error.Message;
    }

    private void Button2_Click(object sender, RoutedEventArgs e)
    {
        HttpWebRequest request =
          (HttpWebRequest)HttpWebRequest.Create(new Uri(baseUri));
        request.BeginGetResponse(new AsyncCallback(ReadCallback),
        request);
    }

    private void ReadCallback(IAsyncResult asynchronousResult)
    {
        HttpWebRequest request =
          (HttpWebRequest)asynchronousResult.AsyncState;
        HttpWebResponse response =
          (HttpWebResponse)request.EndGetResponse(asynchronousResult);
        using (StreamReader streamReader1 =
          new StreamReader(response.GetResponseStream()))
        {
            string resultString = streamReader1.ReadToEnd();
            resultBlock.Text = "Using HttpWebRequest: " + resultString;
        }
    }
}

Answer 1

我宁愿认为你把事情复杂化了。下面是一个非常简单的示例，它通过 HTTPS 从 URI 请求 XML 文档。

它以字符串的形式异步下载 XML，然后使用XDocument.Parse() 加载它。

    private void button2_Click(object sender, RoutedEventArgs e)
    {
        WebClient wc = new WebClient();
        wc.DownloadStringCompleted += HttpsCompleted;
        wc.DownloadStringAsync(new Uri("https://domain/path/file.xml"));
    }

    private void HttpsCompleted(object sender, DownloadStringCompletedEventArgs e)
    {
        if (e.Error == null)
        {
            XDocument xdoc = XDocument.Parse(e.Result, LoadOptions.None);

            this.textBox1.Text = xdoc.FirstNode.ToString();
        }
    }