While loop through XPathNodeIterator not working

Question

I have an XPathNodeIterator named _xpCategories which holds a data like this

        <root>
      <category numberofproducts="0">
        <id>hoved</id>
        <url>/products/hovednavigation</url>
        <name>HOVEDNAVIGATION</name>
        <category numberofproducts="0">
          <id>embalfors</id>
          <url>/products/emballage-og-forsendelse</url>
          <name>Emballage og forsendelse</name>
          <category numberofproducts="0">
            <id>gaveindpak</id>
            <url>/products/gaveindpakning</url>
            <name>Gaveindpakning</name>
            <category numberofproducts="3">
              <id>cellofan</id>
              <url>/products/cellofan</url>
              <name>Cellofan</name>
            </category>
            <category numberofproducts="30">
              <id>gavebånd</id>
              <url>/products/gavebaand</url>
              <name>Gavebånd</name>
            </category>
          </category>
          <category numberofproducts="0">
            <id>kuvkonv</id>
            <url>/products/kuverter-og-konvolutter</url>
            <name>Kuverter og konvolutter</name>
          </category>
          </category>
      </category>
</root>

I want to traverse through each categories in this xml and print id of each one. I had done some code like this.

 while (_xpCategories.MoveNext())
    {
        Console.WriteLine(_xpCategories.Current.SelectSingleNode("id"));

    }

But this loop only works one ,only first category id is getting,then it exist the loop.Can any one point out what I am doing wrong?

Answer 1

you need to modify your XPath expression to select all the categories within your document no matter where they are within the document, as you have 1 parent category with child categories and then child categories within those child categories.

/root/category - this will just select the parent category node (1 node) with many child nodes.

//category - this should select all categories within the XML document no matter where they appear.

take a look here and here for more help

Answer 2

You can use an XPathNavigator with XPathNodeIterator like this

(A modified example from here)

XPathDocument document = new XPathDocument("yourxml.xml");
XPathNavigator navigator = document.CreateNavigator();

XPathNodeIterator _xpCategories = navigator.Select("//category");
_xpCategories.MoveNext();

while (nodesText.MoveNext())
    Console.WriteLine(nodesText.Current.Value);