发布一个RSS辅助类

http://www.cnblogs.com/surfsky/archive/2009/12/03/1616230.html

发布一个RSS辅助类，是使用 XmlSerializer 解析和编码rss xml的。希望对大家有用:)

参考文档：

·http://cyber.law.harvard.edu/rss/rss.html

·http://www.cnblogs.com/rss

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.IO;
using System.Xml;
using System.Xml.Serialization;
using Kingsoc;

namespace Kingsoc.Net
{
    /// <summary>
    /// RSS 单元
    /// </summary>
    public class RssItem
    {
        [XmlElement("title")]       public string Title;
        [XmlElement("link")]        public string Link;
        [XmlElement("description")] public string Description;
        [XmlElement("author")]      public string Author;
        [XmlElement("category")]    public string Category;
        [XmlElement("comments")]    public string Comments;
        [XmlElement("enclosure")]   public string Enclosure;
        [XmlElement("guid")]        public string Guid;
        [XmlElement("pubDate")]     public string PubDate;
        [XmlElement("source")]      public string Source;
    }

    /// <summary>
    /// RSS 频道
    /// </summary>
    [XmlInclude(typeof(RssItem))]
    public class RssChannel
    {
        [XmlElement("title")]           public string Title;
        [XmlElement("link")]            public string Link;
        [XmlElement("description")]     public string Description;

        [XmlElement("language")]        public string Language;
        [XmlElement("copyright")]       public string CopyRight;
        [XmlElement("managingEditor")]  public string ManagingEditor;
        [XmlElement("webMaster")]       public string WebMaster;
        [XmlElement("pubDate")]         public string PubDate;
        [XmlElement("lastBuildDate")]   public string LastBuildDate;
        [XmlElement("category")]        public string Category;
        [XmlElement("docs")]            public string Docs;
        [XmlElement("cloud")]           public string Cloud;
        [XmlElement("ttl")]             public string TTL;
        [XmlElement("image")]           public string Image;
        [XmlElement("rating")]          public string Rating;
        [XmlElement("textInput")]       public string TextInput;
        [XmlElement("skipHours")]       public string SkipHours;
        [XmlElement("skipDays")]        public string SkipDays;

        [XmlElement("item")]
        public List<RssItem> Items = new List<RssItem>();
    }

    /// <summary>
    /// RSS
    /// </summary>
    [XmlInclude(typeof(RssChannel))]
    [XmlRoot("rss")]
    public class Rss
    {
        [XmlElement("channel")]
        public RssChannel Channel;

        // 从XML字符串中解析
        public static Rss LoadXmlString(string xml)
        {
            return SerializationHelper.LoadXmlString(xml, typeof(Rss)) as Rss;
        }

        // 保存为XML字符串
        public string SaveXmlString()
        {
            return SerializationHelper.SaveXmlString(this);
        }

        // 读取指定URL的RSS，并解析之
        public static Rss GetRss(string url)
        {
            string xml = FetchPage(url);
            return SerializationHelper.LoadXmlString(xml, typeof(Rss)) as Rss;
        }

        // 创建示例
        public static Rss CreateSample()
        {
            Rss rss = new Rss();
            RssChannel channel = new RssChannel()
            {
                Title = "Title",
                Link = "Link",
                Description = "Description",
                Language = "zh-cn",
                LastBuildDate = DateTime.Now.ToString(),
                PubDate = DateTime.Now.ToString(),
                TTL = "60"
            };

            channel.Items.Add(new RssItem()
            {
                Title = "Title1",
                Link = "Link",
                Author = "Author",
                PubDate = DateTime.Now.ToString(),
                Guid = "?",
                Description = "Description"
            });
            channel.Items.Add(new RssItem()
            {
                Title = "Title2",
                Link = "Link",
                Author = "Author",
                PubDate = DateTime.Now.ToString(),
                Guid = "?",
                Description = "Description"
            });
            channel.Items.Add(new RssItem()
            {
                Title = "Title3",
                Link = "Link",
                Author = "Author",
                PubDate = DateTime.Now.ToString(),
                Guid = "?",
                Description = "Description"
            });

            rss.Channel = channel;
            return rss;
        }
    }
}

 

使用到的几个附加函数

    public class PageFetcher
    {

        // 获取网页文本
        public static string FetchPage(string url)
        {
            String result;
            HttpWebRequest request = (HttpWebRequest)System.Net.HttpWebRequest.Create(url);
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            Encoding enc = System.Text.Encoding.UTF8
            using (StreamReader sr = new StreamReader(response.GetResponseStream(), enc))
            {
                result = sr.ReadToEnd();
                sr.Close();
            }
            return result;
        }

    }

   public class SerializationHelper
   {
        // object -> xml string
        public static string SaveXmlString(object obj) {return SaveXmlString(obj, null); }
        public static string SaveXmlString(object obj, XmlAttributeOverrides overrides) {return SaveXmlString(obj, obj.GetType(), overrides);}
        public static string SaveXmlString(object obj, Type type, XmlAttributeOverrides overrides)
        {
            System.IO.MemoryStream stream = new MemoryStream();
            using (System.IO.StreamWriter writer = new System.IO.StreamWriter(stream))
            {
                System.Xml.Serialization.XmlSerializer xs = new System.Xml.Serialization.XmlSerializer(type, overrides);
                xs.Serialize(writer, obj);
                writer.Close();
            }
            string str = UnicodeEncoding.UTF8.GetString(stream.GetBuffer());
            return str;
        }

        // xml string -> obj
        public static object LoadXmlString(string xmlString, Type type) {return LoadXmlString(xmlString, type, null);}
        public static object LoadXmlString(string xmlString, Type type, XmlAttributeOverrides overrides)
        {
            byte[] bytes = UnicodeEncoding.UTF8.GetBytes(xmlString);
            System.IO.MemoryStream stream = new MemoryStream(bytes);
            using (System.IO.StreamReader reader = new System.IO.StreamReader(stream))
            {
                System.Xml.Serialization.XmlSerializer xs = new System.Xml.Serialization.XmlSerializer(type, overrides);
                object obj = xs.Deserialize(reader);
                reader.Close();
                return obj;
            }
        }

   }

测试代码：

    Rss rss = Rss.CreateSample();
    Console.WriteLine(rss.SaveXmlString());

    string url = "http://www.cnblogs.com/rss";
    rss = Rss.GetRss(url);