<
xml version="1.0" encoding="utf-8" ><
Schedules><Schedule Date="14/12/2005">
<Location>Place1</Location>
<Time>12:00</Time>
<Description>Set mode</Description>
</Schedule>
<Schedule Date="15/12/2005">
<Location>Place2</Location>
<Time>01:00</Time>
<Description>Select Position</Description>
</Schedule>
</Schedules>
How do I query this to extract data based on criteria I would then like to assign it to a dataset and returned to be loaded on to a datagrid.
This is my code -
XPathNavigator nav;
XPathDocument docNav;
XPathNodeIterator nodeIter;
string expr;
docNav=new XPathDocument(XML_SCHEDULE_FILE);
nav=docNav.CreateNavigator();
expr="/Schedules/Schedule/[Location=Place1]";
nodeIter=nav.Select(expr);
while(nodeIter.MoveNext())
{
string s=nodeIter.ToString();
}
Whatever expression I use, it seems to return a runtime error - "The expression passed to this method should result in a NodeSet".
Can someone please post the right way to query my xml based on a criteria which also includes "and" operator.
Thanks
simple xpath expressions question
dmitry.bulavin
Hi,
http://www.w3schools.com/xpath/xpath_functions.asp#datetime
Use the date-time functions shown in above link to manipulate your conditions...
HTH,
Feitlebaum
Hello there,
Now, I would like to select values with date greater than the current date. Do you know how to do this Any help is much appreciated.
jboekhoff
I see in your code that you are using
XPathNodeIterator
nav.Select
So you will need to use method one of these -
SelectAncestors, SelectChildren, SelectDescendants
HTH,
Yian
mhojlund
Rob Kenny - MSFT
This is cumbersome in XPath 1.0 as it doesn't support date time type. You have to parse your date value using substring function, make it YYYYMMDD, convert to number using number() function and then compare.
Alternatively use EXSLT.NET, which extends XPah and XSLT with date time functions.
1. EXSLT.NET homepage
2. Article at MSDN with samples of date time manipulations
3. eXml - extended XML web server control that supports EXSLT.
Johannes Hartmann
expr="/Schedules/Schedule/[Location=Place1]";
It must be
expr="/Schedules/Schedule/[Location='Place1']";
string s=nodeIter.ToString();
And this one must be
string s=nodeIter.Current.Value;
Operator and in XPath is just "and", e.g.
/Schedules/Schedule/[Location='Place1' and @Date='14/12/2005']
this selects all Schedule elements having Location child with value 'Place1' and Date attributte with value '14/12/2005'.