Problems Navigator Select

[Greg]

Is it possible to filter an XML document twice? I have filter 1, and later
in the code I want to apply filter 2. Filter 2 should be based on the
results from filter 1. I have tried using an XPathNavigator:
XPathDocument xpDocument = new XPathDocument(MyXMLFile);
XPathNavigator xpNavigator = xpDocument.CreateNavigator();

XPathExpression xpeExpr= xpNavigator.Compile(FilterSelectString)
XPathNodeIterator oNavigatorResults = xpNavigator.Select(xpeExpr);

//Later I try something like
XPathExpression xpeExpr2= xpNavigator.Compile(FilterSelectString2)
XPathNodeIterator oNavigatorResults2 =
oNavigatorResults.Current.Select(xpeExpr2)

The behavior is: it doesn't remember the original filter expression. It
acts as if it does a completely new query that is only the second
expression. Any advice much appreciated!

[Oleg Tkachenko [MVP]]

Greg wrote:

Is it possible to filter an XML document twice? I have filter 1, and later
in the code I want to apply filter 2. Filter 2 should be based on the
results from filter 1. I have tried using an XPathNavigator:
XPathDocument xpDocument = new XPathDocument(MyXMLFile);
XPathNavigator xpNavigator = xpDocument.CreateNavigator();

XPathExpression xpeExpr= xpNavigator.Compile(FilterSelectString)
XPathNodeIterator oNavigatorResults = xpNavigator.Select(xpeExpr);

//Later I try something like
XPathExpression xpeExpr2= xpNavigator.Compile(FilterSelectString2)
XPathNodeIterator oNavigatorResults2 =
oNavigatorResults.Current.Select(xpeExpr2)

You forgot to call MoveNext() on oNavigatorResults before accessing its
Current property.
--
Oleg Tkachenko [XML MVP]
http://blog.tkachenko.com