LINQ与ATOM供稿 [英] LINQ with ATOM feeds

问题描述

我想创建一个简单的Silverlight应用程序调用ATOM源，并显示文章标题和提交日期。我发现这很容易与RSS做饲料和LINQ，但我坚持努力做同样的ATOM源。下面的代码产生任何错误，但它也产生没有结果！ ？我想什么

来源ATOM供稿：weblogs.asp.net/scottgu/atom.aspx

来源教程：www.switchonthecode.com/tutorials/silverlight-datagrid-the-basics

源代码：

 使用系统; 
使用System.Collections.Generic; 
使用System.Linq的;使用System.Net 
;使用System.Windows 
;使用System.Windows.Controls的
;使用System.Windows.Documents 
; 
使用System.Windows.Input;使用System.Windows.Media 
; 
使用System.Windows.Media.Animation;使用System.Windows.Shapes 
; 
使用System.Xml.Linq的; 
 
命名空间BasicDataGridTutorial 
 {
公共部分类页：用户控件
 {
公共页面（）
 {
的InitializeComponent（） ; 
} 
 
私人无效btnPopulate_Click（对象发件人，RoutedEventArgs E）
 {
 //所以它不是点击禁用填充按钮两次
 //而该数据被请求
 this.btnPopulate.IsEnabled =假; 
 
 //创建一个新的WebClient对象
 WebClient的客户端=新的WebClient（）; 
 
 //勾当数据被接收
 client.DownloadStringCompleted + = client_DownloadStringCompleted时调用的事件; 
 
 //告诉Web客户端下载数据异步
 client.DownloadStringAsync（
 //新的URI（http://feeds.feedburner.com/SwitchOnTheCode?format= XML））; 
新的URI（http://weblogs.asp.net/scottgu/atom.aspx））; 
} 
 
私人无效client_DownloadStringCompleted（对象发件人，
 DownloadStringCompletedEventArgs E）
 {
 this.btnPopulate.IsEnabled = TRUE; 
如果（e.Error == NULL）
 {
的XDocument文档= XDocument.Parse（e.Result）; 
的XNamespace的xmlns =htt​​p://www.w3.org/2005/Atom; 
 
变种sotcPosts从document.Descendants进入=（的xmlns +项）
选择新SOTCPost 
 {
标题=（字符串）entry.Element号（xmlns + feedEntryContent）值，
日期=（字符串）entry.Element号（xmlns +LASTUPDATED）值
}。 
 
 this.sotcDataGrid.ItemsSource = sotcPosts; 
} 
} 
 
私人无效btnClear_Click（对象发件人，RoutedEventArgs E）
 {
 this.sotcDataGrid.ItemsSource = NULL; 
} 
} 
 
公共类SOTCPost 
 {
公共字符串名称{搞定;组; } 
公共字符串日期{搞定;组; } 
} 
} 
  

解决方案

我建议使用 SyndicationFeed 而不是解析Atom提要自己。它会做处理，你可能没有考虑边缘的情况下更好的工作。

 的XmlReader读卡器= XmlReader.Create（HTTP ：//localhost/feeds/serializedFeed.xml）; 
 SyndicationFeed饲料= SyndicationFeed.Load（读卡器）; 
变种sotcPosts从项目=以feed.Items 
选择新SOTCPost 
 {
标题= item.Title.Text，
日期= item.PublishDate 
 }; 
  

I am trying to create a simple Silverlight application that calls an ATOM feed and displays the article title and submit date. I found this very easy to do with RSS feeds and LINQ but I am stuck trying to do the same with an ATOM feed. The code below produces no errors but it also produced no results! What am I missing?

Source ATOM feed: weblogs.asp.net/scottgu/atom.aspx

Source Tutorial: www.switchonthecode.com/tutorials/silverlight-datagrid-the-basics

Source code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Xml.Linq;

namespace BasicDataGridTutorial
{
  public partial class Page : UserControl
  {
    public Page()
    {
      InitializeComponent();
    }

    private void btnPopulate_Click(object sender, RoutedEventArgs e)
    {
      //disable the populate button so it's not clicked twice
      //while the data is being requested
      this.btnPopulate.IsEnabled = false;

      //make a new WebClient object
      WebClient client = new WebClient();

      //hook the event that's called when the data is received
      client.DownloadStringCompleted += client_DownloadStringCompleted;

      //tell the WebClient to download the data asynchronously
      client.DownloadStringAsync(
          //new Uri("http://feeds.feedburner.com/SwitchOnTheCode?format=xml"));
          new Uri("http://weblogs.asp.net/scottgu/atom.aspx"));
    }

    private void client_DownloadStringCompleted(object sender,
      DownloadStringCompletedEventArgs e)
    {
      this.btnPopulate.IsEnabled = true;
      if (e.Error == null)
      {
        XDocument document = XDocument.Parse(e.Result);
        XNamespace xmlns = "http://www.w3.org/2005/Atom";

        var sotcPosts = from entry in document.Descendants(xmlns+ "entry")
                        select new SOTCPost
                        {
                            Title = (string)entry.Element(xmlns + "feedEntryContent").Value,
                            Date = (string)entry.Element(xmlns + "lastUpdated").Value
                        };

        this.sotcDataGrid.ItemsSource = sotcPosts;
      }
    }

    private void btnClear_Click(object sender, RoutedEventArgs e)
    {
      this.sotcDataGrid.ItemsSource = null;
    }
  }

  public class SOTCPost
  {
    public string Title { get; set; }
    public string Date { get; set; }
  }
}

解决方案

I'd recommend using the SyndicationFeed instead of parsing the ATOM feed yourself. It'll do a better job of handling edge cases you may not have considered.

XmlReader reader = XmlReader.Create("http://localhost/feeds/serializedFeed.xml");
SyndicationFeed feed = SyndicationFeed.Load(reader);
var sotcPosts = from item in feed.Items
	select new SOTCPost
	{
		Title = item.Title.Text,
		Date = item.PublishDate
	};

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