XMLNode转换为XMLDomNode操作，以便支持XPath查询！

var
  Root,Xdn:IXMLDomNode;
begin
  XMLDocument1.LoadFromFile(template.xml');
  Root:=(XMLDocument1.DocumentElement.DOMNode as IXMLDOMNodeRef).GetXMLDOMNode;
  Xdn:=Root.selectSingleNode("xpathquery");