ASP.NET 生成 RSS Feed

前段时间在写RSS Feed。 
 经过了几次的修改，把相关的代码写成了单独的类。 
 感觉重用时还算比较方便的。于是贴出来，大家一起研究研究。

  1using System; 
  2using System.Collections.Generic; 
  3using System.Xml; 
  4    
  5   namespace MyMedia.Utilities 
  6   { 
  7    public class RssBase 
  8    { 
  9    
 10       RssBase constructor#region RssBase constructor 
 11       public RssBase(XmlTextWriter rssWriter) 
 12       { 
 13        this.rssWriter = rssWriter; 
 14       } 
 15       public RssBase(XmlTextWriter rssWriter, bool hasMedia, IList<ItemInfo> items) 
 16       { 
 17           this.rssWriter = rssWriter; 
 18           this.hasMedia = hasMedia; 
 19           this.items = items; 
 20       } 
 21       #endregion 
 22       
 23       [Serializable] 
 24       public sealed class ItemInfo 
 25       { 
 26       
 27       ItemInfo constructor#region ItemInfo constructor 
 28       public ItemInfo() { } 
 29       public ItemInfo(string itemTitle, string itemLink, string itemDescription, string itemPubDate, string itemAuthor, string itemGuid) 
 30       { 
 31           this.itemTitle = itemTitle; 
 32           this.itemLink = itemLink; 
 33           this.itemDescription = itemDescription; 
 34           this.itemAuthor = itemAuthor; 
 35           this.itemGuid = itemGuid; 
 36           this.itemPubDate = itemPubDate; 
 37       } 
 38       public ItemInfo(string itemTitle, string itemLink, string itemDescription, string itemPubDate, string itemAuthor,string itemGuid, string mediaContentUrl, string mediaTitle, string mediaDescription,string mediaThumbUrl, string mediaThumbWidth, string mediaThumbHeight, string mediaAuthor) 
 39       { 
 40           this.itemTitle = itemTitle; 
 41           this.itemLink = itemLink; 
 42           this.itemDescription = itemDescription; 
 43           this.itemPubDate = itemPubDate; 
 44           this.itemAuthor = itemAuthor; 
 45           this.itemGuid = itemGuid; 
 46           this.mediaContentUrl = mediaContentUrl; 
 47           this.mediaTitle = mediaTitle; 
 48           this.mediaDescription = mediaDescription; 
 49           this.mediaThumbUrl = mediaThumbUrl; 
 50           this.mediaThumbWidth = mediaThumbWidth; 
 51           this.mediaThumbHeight = mediaThumbHeight; 
 52           this.mediaAuthor = mediaAuthor; 
 53       } 
 54       #endregion 
 55       
 56      
 57       Internal item variables#region Internal item variables 
 58       // Item variables 
 59        private string itemTitle; 
 60        private string itemLink; 
 61        private string itemDescription; 
 62        private string itemPubDate = DateTime.Now.ToString("r"); 
 63        private string itemDateTaken = DateTime.Now.ToString(); 
 64        private string itemAuthor; 
 65        private string itemGuid; 
 66        // Media variables 
 67        private string mediaContentUrl; 
 68        private string mediaTitle; 
 69        private string mediaDescription; 
 70        private string mediaThumbUrl; 
 71        private string mediaThumbWidth; 
 72        private string mediaThumbHeight; 
 73        private string mediaAuthor; 
 74        #endregion 
 75        
 76       Item properties#region Item properties 
 77
 78        public string ItemTitle 
 79        { 
 80            set { itemTitle = value; } 
 81            get { return itemTitle; } 
 82        } 
 83        public string ItemLink 
 84        { 
 85            set { itemLink = value; } 
 86            get { return itemLink; } 
 87        } 
 88        public string ItemDescription 
 89        { 
 90            set { itemDescription = value; } 
 91            get { return itemDescription; } 
 92        } 
 93        public string ItemPubDate 
 94        { 
 95            set { itemPubDate = value; } 
 96            get { return itemPubDate; } 
 97        } 
 98        public string ItemDateTaken 
 99        { 
100            set { itemDateTaken = value; } 
101            get { return itemDateTaken; } 
102       } 
103       public string ItemAuthor 
104       { 
105           set { itemAuthor = value; } 
106           get { return itemAuthor; } 
107       } 
108       public string ItemGuid 
109       { 
110           set { itemGuid = value; } 
111           get { return itemGuid; } 
112       } 
113       public string MediaContentUrl 
114       { 
115           set { mediaContentUrl = value; } 
116           get { return mediaContentUrl; } 
117       } 
118       public string MediaTitle 
119       { 
120           set { mediaTitle = value; } 
121           get { return mediaTitle; } 
122       } 
123       public string MediaDescription 
124       { 
125           set { mediaDescription = value; } 
126           get { return mediaDescription; } 
127       } 
128       public string MediaThumbUrl 
129       { 
130           set { mediaThumbUrl = value; } 
131           get { return mediaThumbUrl; } 
132       } 
133       public string MediaThumbWidth 
134       { 
135           set { mediaThumbWidth = value; } 
136           get { return mediaThumbWidth; } 
137       } 
138       public string MediaThumbHeight 
139       { 
140           set { mediaThumbHeight = value; } 
141           get { return mediaThumbHeight; } 
142       } 
143       public string MediaAuthor 
144       { 
145           set { mediaAuthor = value; } 
146           get { return mediaAuthor; } 
147       } 
148
149       #endregion 
150       
151       } 
152       
153       Const string#region Const string 
154       private const string TITLE = "MyMedia RSS"; 
155       private const string XMLNS_MEDIA = "http://www.MyWii.com.au"; 
156       private const string XMLNS_DC = "http://purl.org/dc/elements/1.1/"; 
157       private const string LINK = "http://www.MyWii.com.au/"; 
158       private const string DESCRIPTION = "description"; 
159       private const string LANGUAGE = "en-us"; 
160       private const string COPYRIGHT = "Copyright 2006"; 
161       private const string GENERATOR = "MyMedia RSS Generator"; 
162       private const string IMAGE_URL = "http://edu.itbulo.com/UploadFiles_1485/200608/20060831102017260.gif"; 
163       private const string IMAGE_TITLE = "MyWii"; 
164       private const string IMAGE_LINK = "http://www.MyWii.com.au"; 
165       private string PUB_DATE = DateTime.Now.ToString("r"); 
166       private string LAST_BUILD_DATE = DateTime.Now.ToString("r"); 
167       
168       #endregion 
169       
170       Internal member variables#region Internal member variables 
171       private XmlTextWriter rssWriter; 
172       private bool hasMedia; 
173       private IList<ItemInfo> items; 
174       #endregion 
175       
176       Properties#region Properties 
177       public XmlTextWriter RssWriter 
178       { 
179       set { rssWriter = value; } 
180       get { return rssWriter; } 
181       } 
182       public bool HasMedia 
183       { 
184       set { hasMedia = value; } 
185       get { return hasMedia; } 
186       } 
187       public IList<ItemInfo> Items 
188       { 
189       set { items = value; } 
190       get { return items; } 
191       } 
192     #endregion 
193       
194       Private method#region Private method 
195       
196       private void WritePrologue() 
197       { 
198       rssWriter.WriteStartDocument(); 
199       rssWriter.WriteStartElement("rss"); 
200       rssWriter.WriteAttributeString("version", "2.0"); 
201       rssWriter.WriteAttributeString("xmlns:media", XMLNS_MEDIA); 
202       rssWriter.WriteAttributeString("xmlns:dc", XMLNS_DC); 
203       rssWriter.WriteString("\n "); 
204       // Write in channel block 
205       rssWriter.WriteStartElement("channel"); 
206       rssWriter.WriteString("\n "); 
207       rssWriter.WriteElementString("title", TITLE); 
208       rssWriter.WriteString("\n "); 
209       rssWriter.WriteElementString("link", LINK); 
210       rssWriter.WriteString("\n "); 
211       rssWriter.WriteElementString("description", DESCRIPTION); 
212       rssWriter.WriteString("\n "); 
213       rssWriter.WriteElementString("pubDate", PUB_DATE); 
214       rssWriter.WriteString("\n "); 
215       rssWriter.WriteElementString("lastBuildDate", LAST_BUILD_DATE); 
216       rssWriter.WriteString("\n "); 
217       rssWriter.WriteElementString("language", LANGUAGE); 
218       rssWriter.WriteString("\n "); 
219       rssWriter.WriteElementString("copyright", COPYRIGHT); 
220       rssWriter.WriteString("\n "); 
221       rssWriter.WriteElementString("generator", GENERATOR); 
222       rssWriter.WriteString("\n "); 
223       // Write in image block 
224       rssWriter.WriteStartElement("image"); 
225       rssWriter.WriteString("\n "); 
226       rssWriter.WriteElementString("url", IMAGE_URL); 
227       rssWriter.WriteString("\n "); 
228       rssWriter.WriteElementString("title", IMAGE_TITLE); 
229       rssWriter.WriteString("\n "); 
230       rssWriter.WriteElementString("link", IMAGE_LINK); 
231       rssWriter.WriteString("\n "); 
232       rssWriter.WriteEndElement(); 
233       rssWriter.WriteString("\n "); 
234       } 
235       
236       /**//**//**//// <summary> 
237       /// Write in items 
238       /// </summary> 
239       private void WriteItem(ItemInfo item) 
240       { 
241       // Write in item block 
242       rssWriter.WriteStartElement("item"); 
243       rssWriter.WriteString("\n "); 
244       rssWriter.WriteElementString("title", item.ItemTitle); 
245       rssWriter.WriteString("\n "); 
246       rssWriter.WriteElementString("link", item.ItemLink); 
247       rssWriter.WriteString("\n "); 
248       
249       rssWriter.WriteStartElement("description"); 
250       rssWriter.WriteString("\n "); 
251       rssWriter.WriteCData(item.ItemDescription); 
252       rssWriter.WriteString("\n "); 
253       rssWriter.WriteEndElement(); 
254       
255       rssWriter.WriteString("\n "); 
256       rssWriter.WriteElementString("pubDate", item.ItemPubDate); 
257       rssWriter.WriteString("\n "); 
258       rssWriter.WriteElementString("dc:date.Taken", item.ItemDateTaken); 
259       rssWriter.WriteString("\n "); 
260       rssWriter.WriteElementString("author", item.ItemAuthor); 
261       rssWriter.WriteString("\n "); 
262       rssWriter.WriteStartElement("guid"); 
263       rssWriter.WriteAttributeString("isPermaLink", "false"); 
264       rssWriter.WriteString(item.ItemGuid); 
265       rssWriter.WriteEndElement(); 
266       
267       
268       // Write item media here 
269       
270       } 
271       
272       /**//**//**//// <summary> 
273       /// Write in item media 
274       /// </summary> 
275       /// <param name="item">ItemInfo item</param> 
276       private void WriteItemMedia(ItemInfo item) 
277       { 
278       // Write in media 
279       rssWriter.WriteString("\n "); 
280       rssWriter.WriteStartElement("media:content"); 
281       rssWriter.WriteAttributeString("url", item.MediaContentUrl); 
282       rssWriter.WriteAttributeString("type", "image/jpeg"); 
283       rssWriter.WriteEndElement(); 
284       rssWriter.WriteString("\n "); 
285       rssWriter.WriteElementString("media:title", item.MediaTitle); 
286       rssWriter.WriteString("\n "); 
287       rssWriter.WriteStartElement("media:text"); 
288       rssWriter.WriteAttributeString("type", "html"); 
289       rssWriter.WriteString(item.MediaDescription); 
290       rssWriter.WriteEndElement(); 
291       rssWriter.WriteString("\n "); 
292       rssWriter.WriteStartElement("media:thumbnail"); 
293       rssWriter.WriteAttributeString("url", item.MediaThumbUrl); 
294       rssWriter.WriteAttributeString("height", item.MediaThumbHeight); 
295       rssWriter.WriteAttributeString("width", item.MediaThumbWidth); 
296       rssWriter.WriteEndElement(); 
297       rssWriter.WriteString("\n "); 
298       rssWriter.WriteStartElement("media:credit"); 
299       rssWriter.WriteAttributeString("role", "photographer"); 
300       rssWriter.WriteString(item.MediaAuthor); 
301       rssWriter.WriteEndElement(); 
302       rssWriter.WriteString("\n "); 
303       
304       } 
305       
306       /**//**//**//// <summary> 
307       /// Close item element 
308       /// </summary> 
309       private void WriteItemEnd() 
310       { 
311       rssWriter.WriteString("\n "); 
312       rssWriter.WriteEndElement(); 
313       rssWriter.WriteString("\n "); 
314       } 
315       
316       /**//**//**//// <summary> 
317       /// Close all the elements 
318       /// </summary> 
319       private void WriteEnd() 
320       { 
321       rssWriter.WriteEndElement(); 
322       rssWriter.WriteString("\n"); 
323       rssWriter.WriteEndElement(); 
324       rssWriter.WriteEndDocument(); 
325       } 
326       
327       #endregion 
328       
329       /**//**//**//// <summary> 
330       /// Write RSS feed 
331       /// </summary> 
332       public void WriteRSS() 
333       { 
334           WritePrologue(); 
335           foreach (ItemInfo info in items) 
336           { 
337               WriteItem(info); 
338               if (hasMedia) 
339               WriteItemMedia(info); 
340               WriteItemEnd(); 
341           } 
342         WriteEnd(); 
343       }
344 
345
346     }  
347   } 

然后使用一个FeedBase.cs类，调用上面的RssBase类中的方法和属性。代码如下

 1public void GenerateRss()
 2    {
 3        IList<MyMedia.Utilities.RssBase.ItemInfo> items = new List<MyMedia.Utilities.RssBase.ItemInfo>();
 4
 5        // Populate items. 
 6        DataTable dt = new DataTable();
 7        dt.Columns.Add("Title");
 8        dt.Columns.Add("Description");
 9        dt.Columns.Add("PubDate");
10        dt.Columns.Add("Author");
11
12        DataRow dr = dt.NewRow();
13        dr[0] = "t1";
14        dr[1] = "t2";
15        dr[2] = "t3";
16        dr[3] = "t4";
17        dt.Rows.Add(dr);
18        dt.AcceptChanges();
19        this.GridView1.DataSource = dt;
20        GridView1.DataBind();
21        foreach (DataRow row in dt.Rows)
22        {
23            MyMedia.Utilities.RssBase.ItemInfo item = new MyMedia.Utilities.RssBase.ItemInfo(row["Title"].ToString(), "link", row["Description"].ToString(), row["PubDate"].ToString(), row["Author"].ToString(), "guid");
24            items.Add(item);
25        }
26
27        XmlTextWriter xmlWriter = new XmlTextWriter(Response.OutputStream, Encoding.UTF8);
28
29        MyMedia.Utilities.RssBase rssBase = new MyMedia.Utilities.RssBase(xmlWriter, false, items);
30        rssBase.WriteRSS();
31
32        xmlWriter.Flush();
33        xmlWriter.Close();
34
35        Response.ContentEncoding = Encoding.UTF8;
36        Response.ContentType = "text/xml";
37        Response.Cache.SetCacheability(HttpCacheability.Public);
38
39        Response.End();
40    }