RSS Aggregator User Control

I think this is probably the last of the fun user controls that I created for my web sites, but this one was one of the more important ones for my https://www.nocommonground.com website.  When I created NoCommonGround, I wanted a site that would take all the info that I wanted, and put it into one place.  I figured the easiest way to do that, was to integrate all the RSS feeds into one simple place.  Thus, I needed an RSS feed user control.

There are a few bugs with this, I don't do complete checking for nulls every where, but I do in some of the more important places.  I also import my own schema, because I was having problems pulling the schema down from other websites sometimes, and things weren't working right.

Lets have a look at the code:

 <%@ Control Language="C#" ClassName="BlogAgg" %>
<%@ Import Namespace="System.Data" %>

<script runat="server">
    public string BlogRSSFeed = "";
    public string BlogTitle = "";

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            if (BlogRSSFeed == "")
                this.Visible = false;
            else
            {
                try
                {
                    DataSet dsBlog = null;
                    dsBlog = (DataSet)Cache.Get(BlogRSSFeed);
                    if (dsBlog == null)
                    {
                        System.Net.WebProxy myProxy = new System.Net.WebProxy("https://MyProxy/", true);
                        dsBlog = new DataSet();
                        System.Net.WebRequest wr = System.Net.WebRequest.Create(BlogRSSFeed);
                        wr.Proxy = myProxy;
                        System.Net.WebResponse wresp = wr.GetResponse();
                        dsBlog.ReadXmlSchema(Server.MapPath("~") + "\\App_Data\\rss_schema.xsd");
                        dsBlog.ReadXml(wresp.GetResponseStream(), XmlReadMode.IgnoreSchema);
                        Cache.Add(BlogRSSFeed, dsBlog, null, DateTime.Now.AddHours(1), System.Web.Caching.Cache.NoSlidingExpiration, CacheItemPriority.Normal, null);
                    }
                    hlTitleLink.Text = BlogTitle;
                    if (dsBlog.Tables["channel"].Rows[0]["link"] != System.DBNull.Value)
                        hlTitleLink.NavigateUrl = (string)dsBlog.Tables["channel"].Rows[0]["link"];
                    hlTitleLink.Text = BlogTitle;
                    hlTitle.Text = (string)dsBlog.Tables["item"].Rows[0]["title"];
                    hlTitle.NavigateUrl = (string)dsBlog.Tables["item"].Rows[0]["link"];
                    if (dsBlog.Tables["item"].Rows[0]["description"] != System.DBNull.Value)
                        lblEntry.Text = (string)dsBlog.Tables["item"].Rows[0]["description"];
                    else
                        lblEntry.Text = "";
                    
                    int iRows = 10;
                    if (dsBlog.Tables["item"].Rows.Count < iRows)
                        iRows = dsBlog.Tables["item"].Rows.Count;
                    LiteralControl lcStart = new LiteralControl("<ul>");
                    pnlRecent.Controls.Add(lcStart);
                    for (int i = 1; i < iRows; i++)
                    {
                        LiteralControl lcOpen = new LiteralControl("<li>");
                        LiteralControl lcClose = new LiteralControl("</li>");
                        HyperLink hl = new HyperLink();
                        hl.Text = (string)dsBlog.Tables["item"].Rows[i]["Title"];
                        hl.NavigateUrl = (string)dsBlog.Tables["item"].Rows[i]["link"];
                        hl.Target = "_blank";
                        pnlRecent.Controls.Add(lcOpen);
                        pnlRecent.Controls.Add(hl);
                        pnlRecent.Controls.Add(lcClose);
                    }
                    LiteralControl lcStop = new LiteralControl("</ul>");
                    pnlRecent.Controls.Add(lcStop);
                }
                catch (Exception ex)
                {
                    if ((Request.QueryString["debug"] != null) && (Request.QueryString["debug"].ToLower().Equals("true")))
                    {
                        lblEntry.Text = ex.ToString();
                    }
                    else
                    {
                        this.Visible = false;
                    }
                }
            }
        }
    }
</script>

And the HTML:

 <h2 class="title">
    <asp:HyperLink ID="hlTitleLink" runat="server"/></h2>
<div id="BorderDiv">
<table>
    <tr>
        <td style="vertical-align:top; text-align:justify;" width="60%">
            <h2>
            <asp:HyperLink ID="hlTitle" runat="server" Target="_blank" Text="No Recent Entries" />
            </h2>
            <asp:Label ID="lblEntry" style="text-align: justify;" runat="server" >
            </asp:Label>
        </td>
        <td style="vertical-align:top;" width="40%">
            <h2>
                Previous Entries:</h2>
            <asp:Panel ID="pnlRecent" runat="server" />
            
        </td>
    </tr>
</table>
</div>

Overall, it's pretty simple, you can see an example at https://www.nocommonground.com  The photo user controls at the top are just a slight variation on this code, and do some special processing on the data that is handed back so it'll show the picture correctly.

Enjoy!

Comments

• Anonymous
  September 26, 2005
  sorry but not a real need for this since we have this http://www.scottonwriting.net/sowBlog/RssFeed.htm
• Anonymous
  September 26, 2005
  Thanks for the link love, Simone. I do need to update RssFeed sooner than later to support Atom, though. But right now it works equally well with RSS and RDF.
• Anonymous
  September 28, 2005
  Nice updates on the new 1.9 Scott.