How do I get an IXmlNamespaceResolver

Question

I\'m trying to call the XElement.XPathSelectElements() overload that requires an IXmlNamespaceResolver object. Can anyone show me how to get (or make) an IXmlNamespaceResolv

Answer 1

I found this post while searching on how to use the overload of [XPathSelectElements()] to process a SOAP response so, I will post my answer in case it is usefull for others who have a document with several namespace definitions. In my case I have a document like this:

  
    
      
        105
        0
        
          
            111
            Some Value
            Some description
          
          
            222
            Another Value
            Another description
          
          
            333
            And another Value
            And another description
          
        
      
    
  

To create the [XDocument]:

var theDocumentXDoc = XDocument.Parse( theDocumentContent );

To create the [XmlNamespaceManager], I use:

var theNamespaceIndicator = new XmlNamespaceManager( new NameTable() );
theNamespaceIndicator.AddNamespace( "theSoapNS", "http://www.w3.org/2003/05/soap-envelope" );
theNamespaceIndicator.AddNamespace( "noSuffNS" , "http://SomeUrl.com/SomeSection" );

The names I use for the prefixes ( "theSoapNS" and "noSuffNS" ) are arbitrary. Use a name that is convenient for a readable code.

To select the [Envelope] element, I use:

var theEnvelope = theDocumentXDoc.XPathSelectElement( "//theSoapNS:Envelope", theNamespaceIndicator );

To select the [queryResponse] element:

var theQueryResponse = theDocumentXDoc.XPathSelectElement( "//theSoapNS:Envelope/theSoapNS:Body/noSuffNS:queryResponse", theNamespaceIndicator );

To select all details in [theDetails]:

var theDetails = theDocumentXDoc.XPathSelectElement( "//theSoapNS:Envelope/theSoapNS:Body/noSuffNS:queryResponse/noSuffNS:response/noSuffNS:theDetails", theNamespaceIndicator );

Here is an example program (C#6) using the selections:

//The usings you need:
using System;
using System.Linq;
using System.Xml;
using System.Xml.Linq;
using System.Xml.XPath;

namespace ProcessXmlCons
{
    class Inicial
    {
        static void Main(string[] args)
        {
            new Inicial().Tests();
        }

        private void Tests()
        {
            Test01();
        }

        private void Test01()
        {
            var theDocumentContent =
              @"
                    
                        
                        
                            
                                105
                                0
                                
                                    
                                        111
                                        Some Value
                                        Some description
                                    
                                    
                                        222
                                        Another Value
                                        Another description
                                    
                                    
                                        333
                                        And another Value
                                        And another description
                                    
                                
                            
                        
                        
                    
                    ";

            var theDocumentXDoc = XDocument.Parse(theDocumentContent);
            var theNamespaceIndicator = new XmlNamespaceManager(new NameTable());
            theNamespaceIndicator.AddNamespace("theSoapNS", "http://www.w3.org/2003/05/soap-envelope");
            theNamespaceIndicator.AddNamespace("noSuffNS", "http://SomeUrl.com/SomeSection");

            var theEnvelope = theDocumentXDoc.XPathSelectElement("//theSoapNS:Envelope", theNamespaceIndicator);
            Console.WriteLine($"The envelope: {theEnvelope?.ToString()} ");

            var theEnvelopeNotFound = theDocumentXDoc.XPathSelectElement("//Envelope", theNamespaceIndicator);
            Console.WriteLine("".PadRight(120, '_')); //Visual divider
            Console.WriteLine($"The other envelope: \r\n {theEnvelopeNotFound?.ToString()} ");

            var theQueryResponse = theDocumentXDoc.XPathSelectElement("//theSoapNS:Envelope/theSoapNS:Body/noSuffNS:queryResponse", theNamespaceIndicator);
            Console.WriteLine("".PadRight(120, '_')); //Visual divider
            Console.WriteLine($"The query response: \r\n {theQueryResponse?.ToString()} ");

            var theDetails = theDocumentXDoc.XPathSelectElement("//theSoapNS:Envelope/theSoapNS:Body/noSuffNS:queryResponse/noSuffNS:response/noSuffNS:theDetails", theNamespaceIndicator);
            Console.WriteLine("".PadRight(120, '_')); //Visual divider
            Console.WriteLine($"The details: \r\n {theDetails?.ToString()} ");
            Console.WriteLine("".PadRight(120, '_')); //Visual divider

            foreach (var currentDetail in theDetails.Descendants().Where(elementToFilter => elementToFilter.Name.LocalName != "aDetail"))
            {
                Console.WriteLine($"{currentDetail.Name.LocalName}: {currentDetail.Value}");
            }

            //Not optimal. Just to show XPath select within another selection:
            Console.WriteLine("".PadRight(120, '_')); //Visual divider
            Console.WriteLine("Values only:");
            foreach (var currentDetail in theDetails.Descendants())
            {
                var onlyTheValueElement = currentDetail.XPathSelectElement("noSuffNS:theValue", theNamespaceIndicator);
                if (onlyTheValueElement != null)
                {
                    Console.WriteLine($"--> {onlyTheValueElement.Value}");
                }
            }
        }

    } //class Inicial
} //namespace ProcessXmlCons