Question

I want to perform a simple search using xpath, this is my XML

and I want to search the Time nodes and return the Id node value as the result.

this is my code so far, but i dont get any results

XmlNodeList nList = xmlDoc.SelectNodes("//spEvents:Time[. = '" + eventId + "']/parent::node()/spEvents:Times/spEvents:EventTime/spEvents:Time", xmlnsManager);

(Note I am using namespaces)

Thanks
kb

@Jon, my code was working fine with XML to LINQ, as below

return (from feed in xmlDoc_Spektrix.Descendants("Event")
                              from et in feed.Element("Times").Elements("EventTime")
                              where Convert.ToDateTime(et.Element("Time").Value).ToShortDateString() == Convert.ToDateTime(dt).ToShortDateString()
                select feed.Element("Id").Value).ToList();

but since the namespaces were introduced to the xml feed, my code no longer works, which is why i have had to switch to xpath

this code used to work fine, does anyone know why the above code stops working with namespaces?

Answer 1

The correct response to “introducing namespaces broke my query” isn’t “change technology” it’s “fix the query”. This is really easy with LINQ to XML:

// I'm guessing the namespace *really* has the http part on...
XNamespace ns = "http://system.spektrix.com/api/v1/events";

return (from feed in xmlDoc_Spektrix.Descendants(ns + "Event")
        from et in feed.Element(ns + "Times").Elements(ns + "EventTime")
        where (DateTime) et.Element(ns + "Time") == dt
        select feed.Element(ns + "Id").Value).ToList();

Note the simplified (and more correct in the face of culture changes) conversion of an XElement to DateTime as well.