/// <summary>
/// Opens the cached feed file to read the last updated date.
/// </summary>
/// <param name="rssFilename"></param>
/// <returns>The DateTime when it was last updated, or DateTime.MinValue if never updated.</returns>
public DateTime GetLastUpdate(string rssFilename)
{
DateTime dtLastUpdate = DateTime.MinValue; // Never
if (!System.IO.File.Exists(rssFilename))
{
return(dtLastUpdate);
}
XmlTextReader xmlReader = null;
try
{
string strElementName;
XPath xPath = new XPath();
xmlReader = new XmlTextReader(rssFilename);
while (xmlReader.Read())
{
XmlNodeType type = xmlReader.NodeType;
if (type == XmlNodeType.Element)
{
strElementName = xmlReader.Name;
if (!xmlReader.IsEmptyElement && xPath.AddElement(strElementName) == "/rss/channel")
{
if (strElementName == "comshak:lastUpdate")
{
if (!xmlReader.Read() || (xmlReader.NodeType != XmlNodeType.Text))
{
continue;
}
dtLastUpdate = DateTime.Parse(xmlReader.Value);
break;
}
}
}
else if (type == XmlNodeType.EndElement)
{
strElementName = xmlReader.Name;
xPath.RemoveElement(strElementName);
}
}
}
finally
{
if (xmlReader != null)
{
xmlReader.Close();
}
}
return(dtLastUpdate);
}
// Read the items from the rss channel stored on the local storage, and add them to this collection.
// Be sure to keep the date from the existing item (copy it to the current element).
public void Merge()
{
XmlTextReader xmlReader = null;
try
{
if (!File.Exists(m_strFileName))
{
Write();
return;
}
string strElementName;
XPath xPath = new XPath();
RssItem localItem = null;
xmlReader = new XmlTextReader(m_strFileName);
while (xmlReader.Read())
{
XmlNodeType type = xmlReader.NodeType;
if (type == XmlNodeType.Element)
{
strElementName = xmlReader.Name;
if (xmlReader.IsEmptyElement) // Check this first!
{
if (strElementName == "enclosure")
{
localItem.ReadEnclosure(xmlReader);
}
}
else if (xPath.AddElement(strElementName) == "/rss/channel/item")
{
if (!xmlReader.Read())
{
continue;
}
XmlNodeType nt = xmlReader.NodeType;
if ((nt != XmlNodeType.Text) && (nt != XmlNodeType.CDATA))
{
continue;
}
if (localItem == null)
{
localItem = new RssItem();
}
localItem.ReadElement(strElementName, xmlReader.Value, nt);
}
}
else if (type == XmlNodeType.EndElement)
{
strElementName = xmlReader.Name;
xPath.RemoveElement(strElementName);
if ((strElementName == "item") && xPath.Equals("/rss/channel") && (localItem != null))
{
AddIfNew(localItem);
localItem = null;
}
}
}
xmlReader.Close();
xmlReader = null;
Write();
}
catch (Exception ex)
{
Utils.DbgOutExc("RssChannel::Merge()", ex);
}
finally
{
if (xmlReader != null)
{
xmlReader.Close();
}
}
}
