在.NET 3.5中提供了一套全新的接口来实现对RSS和ATOM这两种数据文件的读写。非常方便。下面演示一下

1. 首先要添加一个引用System.ServiceModel.Web

using System.ServiceModel.Syndication;
using System.Xml;

2. 读取RSS的代码

/// <summary>
/// 从一个远程站点读取RSS
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btLoad_Click(object sender, EventArgs e)
{
    SyndicationFeed feed = SyndicationFeed.Load(XmlReader.Create(feedaddress.Text));
    var items = from item in feed.Items
                where item.Title.Text.Contains("VSTS")
                orderby item.PublishDate descending
                select new { Id = item.Id, Title = item.Title.Text };

    dgvResult.DataSource = items.ToArray();
}

效果如下

3. 写入RSS的代码如下

/// <summary>
/// 构造一个RSS
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btCreate_Click(object sender, EventArgs e)
{
    SyndicationFeed feed = new SyndicationFeed(
        "我的博客", 
        "陈希章的博客", 
        new Uri("http://www.xizhang.com/"),
        new[]{
            new SyndicationItem("测试博客标题", "博客内容", new Uri("http://www.xizhang.com/test.aspx")),
            new SyndicationItem("测试博客标题", "博客内容", new Uri("http://www.xizhang.com/test.aspx")),
            new SyndicationItem("测试博客标题", "博客内容", new Uri("http://www.xizhang.com/test.aspx"))
        }
        );

    XmlWriter xw = XmlWriter.Create("rss.xml");
    feed.SaveAsRss20(xw);
    xw.Close();
}

效果如下

4. 结合ashx实现网站的RSS整合

using System;
using System.Web;
using System.Web.Services;
using System.ServiceModel.Syndication;
using System.Xml;

namespace WebApplication1
{
    /// <summary>
    /// $codebehindclassname$ 的摘要说明
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    public class RSS : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            SyndicationFeed feed = new SyndicationFeed(
                "我的博客",
                "陈希章的博客",
                new Uri("http://www.xizhang.com/"),
                new[]{
                    new SyndicationItem("测试博客标题", "博客内容", new Uri("http://www.xizhang.com/test.aspx")),
                    new SyndicationItem("测试博客标题", "博客内容", new Uri("http://www.xizhang.com/test.aspx")),
                    new SyndicationItem("测试博客标题", "博客内容", new Uri("http://www.xizhang.com/test.aspx"))
                }
                );

            XmlWriter xw = XmlWriter.Create(context.Response.OutputStream);
            feed.SaveAsRss20(xw);
            xw.Close();
            context.Response.End();
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}

在客户端读取的效果如下

5. 结合数据库的案例

using System;
using System.Web;
using System.Web.Services;
using System.ServiceModel.Syndication;
using System.Xml;
using System.Data;
using System.Linq;

namespace WebApplication1
{
    /// <summary>
    /// $codebehindclassname$ 的摘要说明
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    public class RSS : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {

            DataTable tb = new DataTable();
            tb.Columns.AddRange(
                new[]{
                    new DataColumn("Title"),
                    new DataColumn("Contents"),
                    new DataColumn("Link")
                });
            //这里可以假设读取一些数据过来

            var items = from DataRow row in tb.Rows
                        select new SyndicationItem(row.Field<string>(0), row.Field<string>(1), new Uri(row.Field<string>(2)));

            SyndicationFeed feed = new SyndicationFeed(
                "我的博客",
                "陈希章的博客",
                new Uri("http://www.xizhang.com/"),
                items.ToArray()
                );

            XmlWriter xw = XmlWriter.Create(context.Response.OutputStream);
            feed.SaveAsRss20(xw);
            xw.Close();
            context.Response.End();
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}