Question

I would like to get an attribute from my xml file. The attribute is on my root. See here an example:

<PriceList ID="003" xmlns="BLA">
  <Items>
    <Item ID="AAK0435">
      <RetailPrice currency="EUR">1.6</RetailPrice>
    </Item>
    <Item ID="AAL0144">
      <RetailPrice currency="EUR">1470</RetailPrice>
    </Item>
  </Items>
</PriceList>

I would like to get the attribute "ID" on the root. I have try something like this but he doesnt come into the foreach loop.

XPathDocument xPriceDocument = new XPathDocument(priceList.FullName, XmlSpace.None);
                            XPathNavigator xPriceNavigator = xPriceDocument.CreateNavigator();

                            foreach (XPathNavigator xPriceListIdNavigator in xPriceNavigator.Select("PriceList"))
                            {
                                priceListId = xPriceListIdNavigator.GetAttribute("ID", "");
                            }

Answer 1

This is a namespace issue.

<PriceList ID="003" xmlns="BLA">

Code xmlns="BLA" in your root element defines a default namespace with URI "BLA". Thus this element and its descendants belong to default namespace "BLA" if the element name doesn t have a namespace prefix. It s easy to forget that an element is in some namespace, if it uses the default namespace, because there is no namespace prefix. Note that default namespace doesn t apply to attributes, only elements.

XPath works with expanded names (that is: a name pair consisting of namespace & local name) and if an element name in your XPath expression doesn t have a namespace prefix, it selects elements that don t belong to any namespace. To use XPath to select elements that belong to some namespace, you need to declare that namespace URI, bind it to a prefix and then use this prefix:element-name combination in your XPath expression.

Namespaces are a fundamental concept in XML. If you are not familiar with namespaces, please take time to learn and understand them.

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