实战篇-六十六行完成简洁的Rss输出类

出处：http://www.cnblogs.com/cyq1162/archive/2010/12/15/1906869.html

 

具体RSS是什么也就不多介绍了，相关的语法和资料，可详见：w3school

Rss 文档示例：

<? xml version="1.0" encoding="utf-8"  ?>
< rss  version ="2.0" >
< channel >
   < title > Autumn Gurden Page </ title >
   < link > http://cyqdata.com </ link >
   < description > Autumn Park is QBlog the official site, created by the passing autumn, based on the framework developed cyqdata data layer supports multiple users, multiple languages, multiple databases(access,mssql,oracle), directory level url and other powerful blog system </ description >
   < item >
     < title > RSS Tutorial </ title >
     < link > http://www.cyqdata.com/rss </ link >
     < description > New RSS tutorial on cyqdata.com </ description >
   </ item >
   < item >
     < title > XML Tutorial </ title >
     < link > http://www.cyqdata.com/cyq1162/rss </ link >
     < description > New XML tutorial on cyqdata.com </ description >
   </ item >
</ channel >
</ rss >  

从示例文档上看，Rss的基本构成：

1：channel一个

2：channel属性若干，有必选和N多可选。

3：channel下有N个Item项，Item也有若干选项。

 

 

为此，简单的说，只要输出以上格式的xml，简单的Rss也即成功了，下面进行代码实战。

 

一：实体类创建

要写成完整点的Rss版，费劲的不是要想怎么输出，而是要知道RSS都有些什么属性，虽然基本文档示例上看相当简洁明了，

不过实现其属性却不是那么一点半点的，为此，prop一个一个敲属性的时候，就费了我不少时间

下面上我辛苦敲写的实体类：

1：RssChannel

RssChannel

public   class  RssChannel
    {
         #region  必选
         private   string  _Title;
         ///   <summary>
         ///  定义频道的标题
         ///   </summary>
         public   string  Title
        {
             get
            {
                 return  _Title;
            }
             set
            {
                _Title  =  value;
            }
        }
         private   string  _Link;
         ///   <summary>
         ///  定义指向频道的超链接
         ///   </summary>
         public   string  Link
        {
             get
            {
                 return  _Link;
            }
             set
            {
                _Link  =  value;
            }
        }
         private   string  _Description;
         ///   <summary>
         ///  描述频道
         ///   </summary>
         public   string  Description
        {
             get
            {
                 return  _Description;
            }
             set
            {
                _Description  =  value;
            }
        }
         #endregion

         #region  可选
         private   string  _Category;
         ///   <summary>
         ///  为 feed 定义所属的一个或多个种类
         ///   </summary>
         public   string  Category
        {
             get
            {
                 return  _Category;
            }
             set
            {
                _Category  =  value;
            }
        }
         private   string  _Cloud;
         ///   <summary>
         ///  注册进程，以获得 feed 更新的立即通知
         ///   </summary>
         public   string  Cloud
        {
             get
            {
                 return  _Cloud;
            }
             set
            {
                _Cloud  =  value;
            }
        }
         private   string  _Copyright;
         ///   <summary>
         ///  告知版权资料
         ///   </summary>
         public   string  Copyright
        {
             get
            {
                 return  _Copyright;
            }
             set
            {
                _Copyright  =  value;
            }
        }
         private   string  _Docs;
         ///   <summary>
         ///  规定指向当前 RSS 文件所用格式说明的 URL
         ///   </summary>
         public   string  Docs
        {
             get
            {
                 return  _Docs;
            }
             set
            {
                _Docs  =  value;
            }
        }
         private   string  _Generator;
         ///   <summary>
         ///  规定指向当前 RSS 文件所用格式说明的 URL
         ///   </summary>
         public   string  Generator
        {
             get
            {
                 return  _Generator;
            }
             set
            {
                _Generator  =  value;
            }
        }
         private   string  _Language  =   " zh-cn " ;
         ///   <summary>
         ///  规定编写 feed 所用的语言
         ///   </summary>
         public   string  Language
        {
             get
            {
                 return  _Language;
            }
             set
            {
                _Language  =  value;
            }
        }

         private   string  _LastBuildDate;
         ///   <summary>
         ///  定义 feed 内容的最后修改日期
         ///   </summary>
         public   string  LastBuildDate
        {
             get
            {
                 return  _LastBuildDate;
            }
             set
            {
                _LastBuildDate  =  value;
            }
        }
         private   string  _ManagingEditor;
         ///   <summary>
         ///  定义 feed 内容编辑的电子邮件地址
         ///   </summary>
         public   string  ManagingEditor
        {
             get
            {
                 return  _ManagingEditor;
            }
             set
            {
                _ManagingEditor  =  value;
            }
        }
         private   string  _PubDate;
         ///   <summary>
         ///  为 feed 的内容定义最后发布日期
         ///   </summary>
         public   string  PubDate
        {
             get
            {
                 return  _PubDate;
            }
             set
            {
                _PubDate  =  value;
            }
        }
         private   string  _Rating;
         ///   <summary>
         ///  feed 的 PICS 级别
         ///   </summary>
         public   string  Rating
        {
             get
            {
                 return  _Rating;
            }
             set
            {
                _Rating  =  value;
            }
        }
         private   string  _SkipDays;
         ///   <summary>
         ///  规定忽略 feed 更新的天
         ///   </summary>
         public   string  SkipDays
        {
             get
            {
                 return  _SkipDays;
            }
             set
            {
                _SkipDays  =  value;
            }
        }
         private   string  _SkipHours;
         ///   <summary>
         ///  规定忽略 feed 更新的小时
         ///   </summary>
         public   string  SkipHours
        {
             get
            {
                 return  _SkipHours;
            }
             set
            {
                _SkipHours  =  value;
            }
        }
         private   string  _TextInput;
         ///   <summary>
         ///  规定应当与 feed 一同显示的文本输入域
         ///   </summary>
         public   string  TextInput
        {
             get
            {
                 return  _TextInput;
            }
             set
            {
                _TextInput  =  value;
            }
        }
         private   string  _Ttl;
         ///   <summary>
         ///  指定从 feed 源更新此 feed 之前，feed 可被缓存的分钟数
         ///   </summary>
         public   string  Ttl
        {
             get
            {
                 return  _Ttl;
            }
             set
            {
                _Ttl  =  value;
            }
        }
         private   string  _WebMaster;
         ///   <summary>
         ///  定义此 feed 的 web 管理员的电子邮件地址
         ///   </summary>
         public   string  WebMaster
        {
             get
            {
                 return  _WebMaster;
            }
             set
            {
                _WebMaster  =  value;
            }
        }
         #endregion

        private string _RssImage;
        /// <summary>
        /// 定义此 feed 的 图片Logo
        /// </summary>
        public string RssImage
        {
            get
            {
                return _RssImage;
            }
            set
            {
                _RssImage = value;
            }
        }
         private  List < RssItem >  _Items  =   new  List < RssItem > ();
         public  List < RssItem >  Items
        {
             get
            {
                 return  _Items;
            }
             set
            {
                _Items  =  value;
            }
        }
    }

2：RssItem

RssItem

public   class  RssItem
    {
         #region  必选
         private   string  _Title;
         ///   <summary>
         ///  定义频道的标题
         ///   </summary>
         public   string  Title
        {
             get
            {
                 return  _Title;
            }
             set
            {
                _Title  =  value;
            }
        }
         private   string  _Link;
         ///   <summary>
         ///  定义指向频道的超链接
         ///   </summary>
         public   string  Link
        {
             get
            {
                 return  _Link;
            }
             set
            {
                _Link  =  value;
            }
        }
         private   string  _Description;
         ///   <summary>
         ///  描述频道
         ///   </summary>
         public   string  Description
        {
             get
            {
                 return  _Description;
            }
             set
            {
                _Description  =  value;
            }
        }
         #endregion

         #region  可选
         private   string  _Category;
         ///   <summary>
         ///  为 feed 定义所属的一个或多个种类
         ///   </summary>
         public   string  Category
        {
             get
            {
                 return  _Category;
            }
             set
            {
                _Category  =  value;
            }
        }
         private   string  _Author;
         ///   <summary>
         ///  规定项目作者的电子邮件地址
         ///   </summary>
         public   string  Author
        {
             get
            {
                 return  _Author;
            }
             set
            {
                _Author  =  value;
            }
        }
         private   string  _Comments;
         ///   <summary>
         ///  允许项目连接到有关此项目的注释（文件）
         ///   </summary>
         public   string  Comments
        {
             get
            {
                 return  _Comments;
            }
             set
            {
                _Comments  =  value;
            }
        }
         private   string  _Enclosure;
         ///   <summary>
         ///  允许将一个媒体文件导入一个项中
         ///   </summary>
         public   string  Enclosure
        {
             get
            {
                 return  _Enclosure;
            }
             set
            {
                _Enclosure  =  value;
            }
        }
         private   string  _Guid;
         ///   <summary>
         ///  为 项目定义一个唯一的标识符
         ///   </summary>
         public   string  Guid
        {
             get
            {
                 return  _Guid;
            }
             set
            {
                _Guid  =  value;
            }
        }
         private   string  _PubDate;
         ///   <summary>
         /// 定义此项目的最后发布日期
         ///   </summary>
         public   string  PubDate
        {
             get
            {
                 return  _PubDate;
            }
             set
            {
                _PubDate  =  value;
            }
        }
         private   string  _Source;
         ///   <summary>
         ///  为此项目指定一个第三方来源
         ///   </summary>
         public   string  Source
        {
             get
            {
                 return  _Source;
            }
             set
            {
                _Source  =  value;
            }
        }
         #endregion
    }

3：RssImage--图片Logo输出

RssImage

public   class  RssImage
    {
         #region  必选
         private   string  _Url;
         ///   <summary>
         ///  图片地址
         ///   </summary>
         public   string  Url
        {
             get
            {
                 return  _Url;
            }
             set
            {
                _Url  =  value;
            }
        }
         private   string  _Title;
         ///   <summary>
         ///  图片标题
         ///   </summary>
         public   string  Title
        {
             get
            {
                 return  _Title;
            }
             set
            {
                _Title  =  value;
            }
        }
         private   string  _Link;
         ///   <summary>
         ///  提供图片的站点链接
         ///   </summary>
         public   string  Link
        {
             get
            {
                 return  _Link;
            }
             set
            {
                _Link  =  value;
            }
        }
         private   string  _Description;
         ///   <summary>
         ///  描述频道
         ///   </summary>
         public   string  Description
        {
             get
            {
                 return  _Description;
            }
             set
            {
                _Description  =  value;
            }
        }
         #endregion
    }

 

最有技术含量的，就是上面三个实体类的敲入了，看着w3规范的属性，一个一个的敲，很累人。

 

OK，有了三个的实体类，接下的事情变的相当简单了。

 

二：创建简洁RSS类

1：新建Rss类--构造函数相当简单的初始化了一下基本数据。

     public   class  Rss
    {
        XmlDocument rssDoc;

        public RssChannel channel;
         public  Rss()
        {
            rssDoc  =   new  XmlDocument( false );
            rssDoc.LoadXml( " <?xml version=/ " 1.0 / "  encoding=/ " utf - 8 / " ?><rss version=/ " 2.0 / " ><channel></channel></rss> " );
            channel  =   new  RssChannel();
        }
    }

2：创建生成RSS--反射实体创建xml元素。

         private   void  BuildRss()
        {
            XmlNode cNode  =  rssDoc.DocumentElement.ChildNodes[ 0 ]; // 取得channel元素
            ForeachCreateChild(cNode, channel); // Channel处理
             if  (channel.RssImage  !=   null )
            {
                ForeachCreateChild(Create( " image " ,  null , cNode), channel.RssImage); // Channel-Image处理
            }
             if  (channel.Items.Count  >   0 )
            {
                 foreach  (RssItem item  in  channel.Items)
                {
                    ForeachCreateChild(Create( " item " ,  null ,cNode), item); // Channel-Items处理
                }
            }
        }

函数分解1：创建节点元素

         private  XmlNode Create( string  name, string  value,XmlNode parent)
        {
            XmlElement xNode = rssDoc.CreateElement(name);
             if  ( string .IsNullOrEmpty(value))
            {
                xNode.InnerXml  =  value;
            }
            parent.AppendChild(xNode  as  XmlNode);
             return  xNode  as  XmlNode;
        }

函数分解2：反射循环创建子节点

         private   void  ForeachCreateChild(XmlNode parent,  object  obj)
        {
             object  propValue  =   null ;
            PropertyInfo[] pis  =  obj.GetType().GetProperties();
             for  ( int  i  =   0 ; i  <  pis.Length; i ++ )
            {
                 if  (pis[i].Name  ==   " Items "   ||  pis[i].Name == " Image " )
                {
                     continue ;
                }
                propValue  =  pis[i].GetValue(obj,  null );
                 if  (propValue  ==   null   ||  propValue  ==  DBNull.Value)
                {
                     continue ;
                }
                 if  (pis[i].Name  ==   " Description " )
                {
                    propValue  =   " <![CDATA[ "   +  propValue.ToString()  +   " ]]> " ;
                }
                Create(pis[i].Name.Substring( 0 ,  1 ).ToLower()  +  pis[i].Name.Substring( 1 ), propValue.ToString(), parent);
            }
        }

3：输出RSS

         public   string  OutXml
        {
             get
            {
                BuildRss();
                 return  rssDoc.OuterXml;
            }
        }

 

至此，一个相当简洁的RSS类就完成了，小小数了一下，RSS类一共花了66代码[要是数上实体类，那代码行就相当的惊人了]，目前在保持良好阅读格式下也只能把代码简化到这种程度了。

 

 三：测试使用示例代码

 1：怎么使用，这个相当简单了

     public   class  RssDemo
    {
         public   string  GetRss()
        {
            Rss rss  =   new  Rss();
            rss.channel.Title  =   " 秋色园 " ;
            rss.channel.Link  =   " http://www.cyqdata.com " ;
            rss.channel.Description  =   " 秋色园-QBlog-Power by Blog.CYQ " ;
             for  ( int  i  =   0 ; i  <   10 ; i ++ )
            {
                RssItem item  =   new  RssItem();
                item.Title  =   string .Format( " 第{0}项 " , i);
                item.Link  =   " http://www.cyqdata.com " ;
                item.Description  =   " 很长很长的内容 " ;

                rss.channel.Items.Add(item);
            }
             return  rss.OutXml;
        }
    }

 

至此，本文就结束了，代码太短，大伙可能刷的一眼就看完了，不过打完收工也到时间了。