Selecting XML nodes defined with namespaces

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While isolating nodes with custom namespace definition, it might be problematic to retrieve the nodes using XPath (SelectSingleNode or SelectNodes methods). Because if the target XML document contains a URN prefix in the node, that has to be defined and explicitly and specified in the SelectSingleNode call. Here is the way to get it into work.

XmlNamespaceManager nsmgr=null; //Declare Namespace manager to track all URNs and prefixes used in target document.

try
{
nsmgr=new XmlNamespaceManager(xdoc.NameTable); //xdoc contains the returned SOAP envelope if successful

nsmgr.AddNamespace("prfx", "https://MyURN.com/"); //add entry about the custom prefix

nsmgr.AddNamespace("soap", "https://schemas.xmlsoap.org/soap/envelope/"); //add entry about default soap prefix available in the SOAP envelope.

}
catch(NullReferenceException nex){Console.WriteLine(nex.Message);} //In case the XML doc wasn’t accessible

XmlNode result = xdoc.SelectSingleNode("//prfx:Operation",nsmgr); //result will now contain the prfx:Operation element or attribute as the case may be.