Solve the SelectNodes and selectSingleNode methods of XML to return a null value problem

Colleague Quality inspection epub documents need to read OPF content, Temporary Internet search for some XML-related code research. The result is that some nodes have not been implemented correctly, and most of the online entries will not solve the problem.

Finally find the problem, if you use a Non-default namespace, you need to add the appropriate namespace.

The code is as follows	Copy Code
XmlDocument xml = new XmlDocument (); Opfurl as Opf file path Xml. Load (Opfurl); XmlNamespaceManager nsmgr = new XmlNamespaceManager (XML. NameTable); Http://www.idpf.org/2007/opf for the XML document namespace Nsmgr.addnamespace ("ns", "Http://www.idpf.org/2007/opf"); Reference for the festival roll Call XmlNodeList reference = XML. SelectNodes ("//ns:reference", nsmgr);