/// <summary>
/// Create a string object with an RSS 2.0 (XML) feed, generated by using the passed params.
/// <para>SQL must return fields in the following order:</para>
/// <para>1. Unique ID for the record, which is appended to the "redirect" param below to create a link to the content.</para>
/// <para>2. Title for the article.</para>
/// <para>3. Short description of the article (up to 500 characters, or will be cropped to 500).</para>
/// <para>4. Date of the article.</para>
/// </summary>
/// <example>
/// <code>
/// using Argentini.Halide;
/// ...
/// string result = H3Xml.BuildRss("SELECT TOP 10 ID, headline, content, date, content FROM News;", "MyDatabase", rssDate, "Feed Title", "http://nonsequiturs.com", "This is the pocketkaos weekly feed.", "(c)opyright 2007", "http://nonsequiturs.com/rss/redirect.aspx?ID=");
/// </code>
/// </example>
/// <param name="sql">SQL SELECT statement for pulling data</param>
/// <param name="connectionStringName">Connection string name to use for SQL access.</param>
/// <param name="rssDate">Date of the feed itself</param>
/// <param name="title">Title of the feed</param>
/// <param name="link">Link to the source web site (e.g. http://nonsequiturs.com).</param>
/// <param name="description">Description of the feed (up to 500 characters)</param>
/// <param name="copyright">Copyright text</param>
/// <param name="redirect">Path to use for redirection (e.g. "http://nonsequiturs.com/rss/redirect.aspx?ID="). The first column returned will be appended to the end of this string for you.
/// Passed param is pulled from SQL and appended. This is also used as a unique GUID for the item.</param>
/// <param name="feedUrl">Fully qualified URL to the generated feed. This is only used to generate an ATOM self-referral tag within the feed itself.</param>
/// <returns>A string containing the XML for the RSS feed.</returns>
public static String BuildRss(String sql, String connectionStringName, String rssDate, String title, String link, String description, String copyright, String redirect, String feedUrl)
{
System.DateTime thedate = new System.DateTime();
StringWriter sw = new StringWriter();
XmlTextWriter xml = new XmlTextWriter(sw);
thedate = Convert.ToDateTime(rssDate);
xml.Formatting = Formatting.Indented;
xml.Indentation = 1;
xml.IndentChar = (char)9;
xml.WriteStartDocument();
#region Write document header
xml.WriteStartElement("rss");
xml.WriteAttributeString("version", "2.0");
xml.WriteAttributeString("xmlns:atom", "http://www.w3.org/2005/Atom");
#endregion
xml.WriteStartElement("channel");
#region Write channel information
xml.WriteStartElement("title"); xml.WriteString(title); xml.WriteEndElement();
xml.WriteStartElement("link"); xml.WriteString(link); xml.WriteEndElement();
xml.WriteStartElement("description"); xml.WriteString(description); xml.WriteEndElement();
xml.WriteStartElement("language"); xml.WriteString("en-us"); xml.WriteEndElement();
xml.WriteStartElement("copyright"); xml.WriteString(copyright); xml.WriteEndElement();
xml.WriteStartElement("pubDate"); xml.WriteString(H3Temporal.DateFormat(thedate, Halide.H3Temporal.DateFormats.Rss2)); xml.WriteEndElement();
xml.WriteStartElement("lastBuildDate"); xml.WriteString(H3Temporal.DateFormat(DateTime.Now, Halide.H3Temporal.DateFormats.Rss2)); xml.WriteEndElement();
xml.WriteStartElement("ttl"); xml.WriteString("5"); xml.WriteEndElement();
xml.WriteStartElement("generator"); xml.WriteString("Halide"); xml.WriteEndElement();
#endregion
#region Read in items from database
Halide.H3Reader reader = new Halide.H3Reader(sql, connectionStringName);
while (reader.Read())
{
xml.WriteStartElement("item");
xml.WriteStartElement("title"); xml.WriteString(H3Text.StripHtml(H3Text.HtmlRemoveSymbols(reader[1]), true, false)); xml.WriteEndElement();
xml.WriteStartElement("link"); xml.WriteString(redirect + reader[0]); xml.WriteEndElement();
string desc = H3Text.StripHtml(reader[2], true, false).Replace("\r", " ").Replace("\n", "");
String suffix = "";
if (desc.Length > 400)
{
desc = H3Text.Crop(desc, 400, Halide.H3Text.CropType.Characters, " .,:?!([");
suffix = "...";
}
while (desc.IndexOf(" ") >= 0)
{
desc = desc.Replace(" ", " ");
}
desc = desc.Replace(" ", " ");
desc = desc.Replace(" ", " ");
desc = desc.Trim();
if (desc.LastIndexOf("&") > (desc.Length - 8))
{
desc = desc.Substring(0, desc.LastIndexOf("&"));
}
desc = desc.Trim() + suffix;
xml.WriteStartElement("description"); xml.WriteString(desc); xml.WriteEndElement();
xml.WriteStartElement("pubDate"); xml.WriteString(H3Temporal.DateFormat(Convert.ToDateTime(reader.GetString(3)), Halide.H3Temporal.DateFormats.Rss2)); xml.WriteEndElement();
xml.WriteStartElement("guid"); xml.WriteString(redirect + reader[0]); xml.WriteEndElement();
xml.WriteEndElement();
}
reader.Close();
#endregion
#region Write out atom-compliant self-link
xml.WriteStartElement("atom:link");
xml.WriteAttributeString("href", feedUrl);
xml.WriteAttributeString("rel", "self");
xml.WriteAttributeString("type", "application/rss+xml");
xml.WriteEndElement();
#endregion
xml.WriteEndElement();
xml.WriteEndElement();
xml.WriteEndDocument();
xml.Close();
string[] delim = { "\r\n" };
string[] decl = sw.ToString().Split(delim, StringSplitOptions.None);
decl[0] = decl[0].Replace("utf-16", "ISO-8859-1");
string feed = "";
for (int x = 0; x < decl.Length; x++)
{
feed += decl[x] + "\r\n";
}
return (feed);
}
