一個簡單asp.net下Web RSS控件

 

一個簡單asp.net下Web RSS控件，支持數據綁定列設置，綁定到DataTable數據源。  設計模式中輸出位html的幫助信息。正式用的時候。WebRss.OutRss();  輸出標準XML格式的RSS文檔

namespace WebControls
...{



    public class WebRSS : WebControl
    ...{
        private object m_DataSource;

        public WebRSS()
        ...{
            m_ItemDescriptionField = "Description";
            m_ItemLinkField = "Link";
            m_ItemPubDateField = "PubDate";
            m_ItemTitleField = "Title";
            
            this.Init += new EventHandler(WebRSS_Init);
        }

        void WebRSS_Init(object sender, EventArgs e)
        ...{
            
        }


        private string m_Title, m_Link, m_Description, m_Language, m_ItemTitleField, m_ItemDescriptionField, m_ItemPubDateField, m_ItemLinkField;


        [Category("RSS基本屬性")]
        [Description("RSS頻道名稱")]
        public string Title
        ...{
            get...{ return m_Title;}
            set ...{ m_Title = value; }
        }

        [Category("RSS基本屬性")]
        [Description("RSS頻道連接地址")]
        public string Link
        ...{
            get ...{ return m_Link; }
            set ...{ m_Link = value; }
        }

        [Category("RSS基本屬性")]
        [Description("RSS頻道說明")]
        public string Description
        ...{
            get ...{ return m_Description; }
            set ...{ m_Description = value; }
        }

        [Category("RSS基本屬性")]
        [Description("RSS頻道語言")]
        public string Language
        ...{
            get ...{ return m_Language; }
            set ...{ m_Language = value; }
        }

        [Category("RSS項綁定屬性")]
        [Description("RSS項標題列名")]
        public string ItemTitleField
        ...{
            get ...{ return m_ItemTitleField; }
            set ...{ m_ItemTitleField = value; }
        }

        [Category("RSS項綁定屬性")]
        [Description("RSS項描述列名")]
        public string ItemDescriptionField
        ...{
            get ...{ return m_ItemDescriptionField; }
            set ...{ m_ItemDescriptionField = value; }
        }

        [Category("RSS項綁定屬性")]
        [Description("RSS項發佈時間列名")]
        public string ItemPubDateField
        ...{
            get ...{ return m_ItemPubDateField; }
            set ...{ m_ItemPubDateField = value; }
        }

        [Category("RSS項綁定屬性")]
        [Description("RSS項連接地址列名")]
        public string ItemLinkField
        ...{
            get ...{ return m_ItemLinkField; }
            set ...{ m_ItemLinkField = value; }
        }

        


        [Category("RSS項綁定屬性")]
        [Description("RSS項數據源")]
        public object DataSource
        ...{
            get ...{ return m_DataSource; }
            set ...{ m_DataSource = value; }
        }

        
        private void DataBindItem()
        ...{
            /**//**/
           string templet = @"<asp:Repeater id=""myRepeater"" runat=""server"">
<ItemTemplate><item>
<title><%#DataBinder.Eval(Container.DataItem,"""+m_ItemTitleField+@"""%></title>
<description><![CDATA[<%#DataBinder.Eval(Container.DataItem,""" + m_ItemDescriptionField + @"""%>]]></description>
<pubDate><%#DataBinder.Eval(Container.DataItem,""" + m_ItemPubDateField + @"""%></pubDate>
<link><%#DataBinder.Eval(Container.DataItem, """ + m_ItemLinkField + @""" %></link>
</item>
</ItemTemplate>
</asp:Repeater>
";
            

            Repeater r = new Repeater();
            this.Controls.Add(r);
            

        }


        /**//// <summary>
        /// 輸出RSS聚合內容
        /// </summary>
        public void OutRss()
        ...{
            StringBuilder rss = new StringBuilder();
            rss.AppendLine("<rss version="2.0">");
            rss.AppendLine("<channel>");
            rss.AppendLine("<title>"+m_Title +"</title>");
            rss.AppendLine("<link>" + m_Link + "</link>");
            rss.AppendLine("<description>" + m_Description + "</description>");
            rss.AppendLine("<language>zh-cn</language>");
            rss.AppendLine("<pubdate>" + DateTime.Now.ToString() + "</pubdate>");

            System.Collections.IEnumerable ie = m_DataSource as System.Collections.IEnumerable;
            if (ie != null)
            ...{
                System.Collections.IEnumerator ie2 = ie.GetEnumerator();
                DataRowView dr;
                while (ie2.MoveNext())
                ...{
                    dr = ie2.Current as DataRowView;
                    rss.AppendLine(@"<item>
<title>" + Common.ToString(dr[m_ItemTitleField]) + @"</title>
<description><![CDATA[" + Common.ToString(dr[m_ItemDescriptionField]) + @"]]></description>
<pubDate>" + Common.ToString(dr[m_ItemPubDateField]) + @"</pubDate>
<link>" + Common.ToString(dr[m_ItemLinkField]) + @"</link>
</item>");

                }
            }

            rss.AppendLine("</channel>");
            rss.AppendLine("</rss>");
            if (Page.Response != null)
            ...{
                Page.Response.Clear();
                Page.Response.Expires = 0;
                Page.Response.ContentType = "text/xml";
                Page.Response.ContentEncoding = Encoding.UTF8;
                Page.Response.Write(rss.ToString());
                Page.Response.End();
            }

        }



        protected override string TagName
        ...{
            get
            ...{
                return "channel";
            }
        }



        protected override void RenderContents(HtmlTextWriter writer)
        ...{
            DataBindItem();

            if (DesignMode)
            ...{
                writer.WriteLine("標題：" + m_Title); writer.WriteBreak();
                writer.WriteLine("連接：" + m_Link); writer.WriteBreak();
                writer.WriteLine("描述：" + m_Description); writer.WriteBreak();
                writer.WriteLine("語言：" + m_Language); writer.WriteBreak();
                for (int i = 0; i < 3; i++)
                ...{
                    writer.WriteBreak();
                    writer.WriteLine("RSS項標題：綁定列（" + m_ItemTitleField + ")"); writer.WriteBreak();
                    writer.WriteLine("RSS項連接：綁定列（" + m_ItemLinkField + ")"); writer.WriteBreak();
                    writer.WriteLine("RSS項說明：綁定列（" + m_ItemDescriptionField + ")"); writer.WriteBreak();
                    writer.WriteLine("RSS項時間：綁定列（" + m_ItemPubDateField + ")"); writer.WriteBreak();
                }
            }
            else
            ...{
                writer.WriteLine("應該輸出爲XML格式。"); writer.WriteBreak();
            }
            base.RenderContents(writer);
        }

        


    }
}