c#解析RSS新聞源

       昨天弄了一天，終於成功解析了南方週末的RSS新聞源，因爲我做的是例子程序，所以是在控制檯下寫的，但基本思路應該是差不多的~~

RSS類的設計如下

 class rss
    {
        public struct Channel
        {
            public string Title;
            public Hashtable Items;
        }

        public struct Item
        {
            public string Title;
            public string Description;
            public string Link;
            public string author；
            public string pubdate；
        } 
    }

channel下面包含Title和Item兩個變量，TItle存的是該RSS源的名稱，Item存放的是該RSS源中的新聞列表，Item裏面的每一個變量都是Struct Item類型的。

 首先是加載XML文檔，.NET提供了很多種加載XML的方法，具體的可以參考微軟的幫助手冊

 本文采用XmlDoucment.Load方法，下面是具體的代碼

            XmlTextReader Reader = new XmlTextReader("http://www.infzm.com/rss/home/rss2.0.xml");
          XmlDocument xmlDoc= new XmlDocument();
          xmlDoc.Load(Reader);

先寫了一個FoundChildNode（XmlNode Node, string Name）函數去查找指定Node結點下名稱爲Name的子節點

private XmlNode FoundChildNode(XmlNode Node, string Name)
        {
            XmlNode childlNode = null;
            for (int i = 0; i < Node.ChildNodes.Count; i++)
            {
                if (Node.ChildNodes[i].Name == Name && Node.ChildNodes[i].ChildNodes.Count > 0)
                {
                    childlNode = Node.ChildNodes[i];
                    return childlNode;
                }
            }
            return childlNode;
        }

然後開始遍歷所有結點，找到我們所需要的標籤

          XmlNode rssNode = FoundChildNode(xmlDoc, "rss");
          XmlNode channelNode = FoundChildNode(rssNode, "channel");
          rss.Channel channel = new rss.Channel();
          channel.Items = new Hashtable();
          for (int i = 0; i < channelNode.ChildNodes.Count;i++ )
          {
              switch (channelNode.ChildNodes[i].Name)
              {
                  case "title":
                      {
                          channel.Title = channelNode.ChildNodes[i].InnerText;
                          break;
                      }
                  case "item":
                      {
                          rss.Item item = this.getRssItem(channelNode.ChildNodes[i]);
                          channel.Items.Add(channel.Items.Count, item);
                          break;
                      }
              }

getRssItem函數是遍歷所有Item結點的子節點，然後將相應的內容存入Item中，也就是將我們需要的新聞標題，時間，描述等等存入Item中。

 private rss.Item getRssItem(XmlNode Node)
        {
            rss.Item item = new rss.Item();
            for (int i = 0; i < Node.ChildNodes.Count; i++)
            {
                if (Node.ChildNodes[i].Name == "title")
                {
                    item.Title = Node.ChildNodes[i].InnerText;
                }
                else if (Node.ChildNodes[i].Name == "description")
                {
                    item.Description = Node.ChildNodes[i].InnerText;
                }
                else if (Node.ChildNodes[i].Name == "link")
                {
                    item.Link = Node.ChildNodes[i].InnerText;
                }
                else if（Node.ChildNodes[i].Name == "author"）
                {                   

                    item.author = Node.ChildNodes[i].InnerText;

}
else if（Node.ChildNodes[i].Name == "pubdate"）
{

                 item.pubdate = Node.ChildNodes[i].InnerText;
                }

} return item; }最後在控制檯下輸出RSS內容

  static void Main(String[] args)
        {
            Program program = new Program();
            rss.Channel readChannel = new rss.Channel();
            readChannel=program.ReadXml();
            Console.WriteLine(readChannel.Title);
            for (int i = 0; i < readChannel.Items.Count; i++)
            {
                rss.Item item = (rss.Item)readChannel.Items[i];
                Console.WriteLine(item.Title);
                Console.WriteLine(item.Link);
                Console.WriteLine(item.Description);
                Console.WriteLine(item.author);
                Console.WriteLine(item.pubdate);
             }
        }

Console.WriteLine(item.Link);

以上大部分思路都是來自於http://tianxie3633.blog.163.com/blog/static/660254002009112084946324/

本文是在控制檯下寫的，請不要隨便複製粘貼，請在理解的基礎上靈活運用，我貼出整個代碼給初學者參考

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Collections;

namespace RssClass
{
    class Program
    {
        private XmlNode FoundChildNode(XmlNode Node, string Name)
        {
            XmlNode childlNode = null;
            for (int i = 0; i < Node.ChildNodes.Count; i++)
            {
                if (Node.ChildNodes[i].Name == Name && Node.ChildNodes[i].ChildNodes.Count > 0)
                {
                    childlNode = Node.ChildNodes[i];
                    return childlNode;
                }
            }
            return childlNode;
        }
        private rss.Item getRssItem(XmlNode Node)
        {
            rss.Item item = new rss.Item();
            for (int i = 0; i < Node.ChildNodes.Count; i++)
            {
                if (Node.ChildNodes[i].Name == "title")
                {
                    item.Title = Node.ChildNodes[i].InnerText;
                }
                else if (Node.ChildNodes[i].Name == "description")
                {
                    item.Description = Node.ChildNodes[i].InnerText;
                }
                else if (Node.ChildNodes[i].Name == "link")
                {
                    item.Link = Node.ChildNodes[i].InnerText;
                }
            }
            return item;
        }
        public rss.Channel ReadXml()
        {
          XmlTextReader Reader = new XmlTextReader("http://www.infzm.com/rss/home/rss2.0.xml");
         // XmlValidatingReader Valid = new XmlValidatingReader(Reader);
         // Valid.ValidationType = ValidationType.None;
          XmlDocument xmlDoc= new XmlDocument();
          xmlDoc.Load(Reader);
          XmlNode rssNode = FoundChildNode(xmlDoc, "rss");
          XmlNode channelNode = FoundChildNode(rssNode, "channel");
          rss.Channel channel = new rss.Channel();
          channel.Items = new Hashtable();
          for (int i = 0; i < channelNode.ChildNodes.Count;i++ )
          {
              switch (channelNode.ChildNodes[i].Name)
              {
                  case "title":
                      {
                          channel.Title = channelNode.ChildNodes[i].InnerText;
                          break;
                      }
                  case "item":
                      {
                          rss.Item item = this.getRssItem(channelNode.ChildNodes[i]);
                          channel.Items.Add(channel.Items.Count, item);
                          break;
                      }
              }
          }
          return channel;

        }
        static void Main(String[] args)
        {
            Program program = new Program();
            rss.Channel readChannel = new rss.Channel();
            readChannel=program.ReadXml();
            Console.WriteLine(readChannel.Title);
            for (int i = 0; i < readChannel.Items.Count; i++)
            {
                rss.Item item = (rss.Item)readChannel.Items[i];
                Console.WriteLine(item.Title);
                Console.WriteLine(item.Link);
                Console.WriteLine(item.Description);
            }
        }
        
        
    }
    class rss
    {
        public struct Channel
        {
            public string Title;
            public Hashtable Items;
        }

        public struct Item
        {
            public string Title;
            public string Description;
            public string Link;
        } 
    }
}