读取XML和未声明的名称空间

Question

I got this error message when I try to read the XMLfile

 Unhandled Exception: System.Xml.XmlException: 'xi' is an undeclared namespace. Line 12, position 18.
   at System.Xml.XmlTextReaderImpl.Throw(Exception e)
   at System.Xml.XmlTextReaderImpl.Throw(String res, String arg, Int32 lineNo, Int32 linePos)
   at System.Xml.XmlTextReaderImpl.LookupNamespace(NodeData node)
   at System.Xml.XmlTextReaderImpl.ElementNamespaceLookup()
   at System.Xml.XmlTextReaderImpl.ParseAttributes()
   at System.Xml.XmlTextReaderImpl.ParseElement()
   at System.Xml.XmlTextReaderImpl.ParseElementContent()
   at System.Xml.XmlTextReaderImpl.Read()
   at System.Xml.XmlTextReader.Read()

Code to read XML:

   XmlTextReader reader = new XmlTextReader("file.xml");
    while (reader.Read())
    {
        // Do some work here on the data.
        Console.WriteLine(reader.Name);
    }
    Console.ReadLine();

The xml file:

<?xml version="1.0" encoding="ISO-8859-1"?>    
<doh> 
        <!-- Available Resources-->
        <servers>
                <xi:include href="file.xml"/>
        </servers>

Answer 1

I assume that you are wanting to use XInclude. You must define which namespace the xi prefix maps to. The easiest why is too include the namespace mapping in the root element.

  <doh xmlns:xi="http://www.w3.org/2001/XInclude">

Note that the XmlTextReader will not include the "file.xml". You will have to 'include' by some other code. A good background paper on the XInclude can be found on MSDN at http://msdn.microsoft.com/en-us/library/aa302291.aspx