Windows Phone 7 网络编程之RSS阅读器
实现一个RSS阅读器，通过你输入的RSS地址来获取RSS的信息列表和查看RSS文章中的详细内容。RSS阅读器是使用了WebClient类来获取网络上的RSS的信息，然后再转化为自己定义好的RSS实体类对象的列表，最后绑定到页面上。
（1） RSS实体类和RSS服务类
RssItem.cs
using System.Net;
using System.Text.RegularExpressions;
namespace WindowsPhone.Helpers
{
/// <summary>
/// RSS对象类
/// </summary>
public class RssItem
{
/// <summary>
/// 初始化一个RSS目录
/// </summary>
/// <param name="title">标题</param>
/// <param name="summary">内容</param>
/// <param name="publishedDate">发表事件</param>
/// <param name="url">文章地址</param>
public RssItem(string title, string summary, string publishedDate, string url)
{
Title = title;
Summary = summary;
PublishedDate = publishedDate;
Url = url;
//解析html
PlainSummary = HttpUtility.HtmlDecode(Regex.Replace(summary, "<[^>]+?>", ""));
}
//标题
public string Title { get; set; }
//内容
public string Summary { get; set; }
//发表时间
public string PublishedDate { get; set; }
//文章地址
public string Url { get; set; }
//解析的文本内容
public string PlainSummary { get; set; }
}
}
RssService.cs
using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.ServiceModel.Syndication;
using System.Xml;
namespace WindowsPhone.Helpers
{
/// <summary>
/// 获取网络RSS服务类
/// </summary>
public static class RssService
{
/// <summary>
/// 获取RSS目录列表
/// </summary>
/// <param name="rssFeed">RSS的网络地址</param>
/// <param name="onGetRssItemsCompleted">获取完成事件</param>
public static void GetRssItems(string rssFeed, Action<IEnumerable<RssItem>> onGetRssItemsCompleted = null, Action<Exception> onError = null, Action onFinally = null)
{
WebClient webClient = new WebClient();
//注册webClient读取完成事件
webClient.OpenReadCompleted += delegate(object sender, OpenReadCompletedEventArgs e)
{
try
{
if (e.Error != null)
{
if (onError != null)
{
onError(e.Error);
}
return;
}
//将网络获取的信息转化成RSS实体类
List<RssItem> rssItems = new List<RssItem>();
Stream stream = e.Result;
XmlReader response = XmlReader.Create(stream);
SyndicationFeed feeds = SyndicationFeed.Load(response);
foreach (SyndicationItem f in feeds.Items)
{
RssItem rssItem = new RssItem(f.Title.Text, f.Summary.Text, f.PublishDate.ToString(), f.Links[0].Uri.AbsoluteUri);
rssItems.Add(rssItem);
}
//通知完成返回事件执行
if (onGetRssItemsCompleted != null)
{
onGetRssItemsCompleted(rssItems);
}
}
finally
{
if (onFinally != null)
{
onFinally();
}
}
};
webClient.OpenReadAsync(new Uri(rssFeed));
}
}
}
（2） RSS页面展示
MainPage.xaml
<phone:PhoneApplicationPage
x:Class="ReadRssItemsSample.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="768"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource PhoneForegroundBrush}"
SupportedOrientations="Portrait" Orientation="Portrait"
shell:SystemTray.IsVisible="True">
<Grid x:Name="LayoutRoot" Background="Transparent">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="12,17,0,28">
<TextBlock x:Name="ApplicationTitle" Text="RSS阅读器" Style="{StaticResource PhoneTextNormalStyle}"/>
</StackPanel>
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<TextBlock FontSize="30" Grid.Row="1" Height="49" HorizontalAlignment="Left" Margin="0,6,0,0" Name="textBlock1" Text="RSS地址" VerticalAlignment="Top" Width="116" />
<TextBox Grid.Row="1" Height="72" HorizontalAlignment="Left" Margin="107,0,0,0" Name="rssURL" Text="http://www.cnblogs.com/rss" VerticalAlignment="Top" Width="349" />
<Button Content="加载 RSS" Click="Button_Click" Margin="-6,72,6,552" Grid.Row="1" />
<ListBox x:Name="listbox" Grid.Row="1" SelectionChanged="OnSelectionChanged" Margin="0,150,6,-11">
<ListBox.ItemTemplate >
<DataTemplate>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="60" />
</Grid.RowDefinitions>
<TextBlock Grid.Row="0" Text="{Binding Title}" Foreground="Blue" />
<TextBlock Grid.Row="1" Text="{Binding PublishedDate}" Foreground="Green" />
<TextBlock Grid.Row="2" TextWrapping="Wrap" Text="{Binding PlainSummary}" />
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Grid>
</phone:PhoneApplicationPage>
MainPage.xaml.cs
using System.Windows;
using System.Windows.Controls;
using Microsoft.Phone.Controls;
using WindowsPhone.Helpers;
namespace ReadRssItemsSample
{
public partial class MainPage : PhoneApplicationPage
{
private string WindowsPhoneBlogPosts = "";
public MainPage()
{
InitializeComponent();
}
private void Button_Click(object sender, RoutedEventArgs e)
{
if (rssURL.Text != "")
{
WindowsPhoneBlogPosts = rssURL.Text;
}
else
{
MessageBox.Show("请输入RSS地址！");
return;
}
//加载RSS列表
RssService.GetRssItems(
WindowsPhoneBlogPosts,
(items) => { listbox.ItemsSource = items; },
(exception) => { MessageBox.Show(exception.Message); },
null
);
}
//查看文章的详细内容
private void OnSelectionChanged(object sender, SelectionChangedEventArgs e)
{
if (listbox.SelectedItem == null)
return;
var template = (RssItem)listbox.SelectedItem;
MessageBox.Show(template.PlainSummary);
listbox.SelectedItem = null;
}
}
}
（3）程序运行的效果如下
