Table of contents

Appendices

B.3 Default Namespace Lookup

The following describes in pseudo code the algorithm used in the isDefaultNamespace method of the Node interface. This methods ignores DOM Level 1 nodes.

boolean isDefaultNamespace(in DOMString namespaceURI)
{
  switch (nodeType) {
  case ELEMENT_NODE:  
     if ( Element has no prefix )
     {
          return (Element's namespace == namespaceURI);
     }
     if ( Element has attributes and there is a valid DOM Level 2 
          default namespace declaration, i.e. Attr's localName == "xmlns" )
     {
	  return (Attr's value == namespaceURI);
     }

     if ( Element has an ancestor Element )
         // EntityReferences may have to be skipped to get to it
     {
          return ancestorElement.isDefaultNamespace(namespaceURI);
     }
     else {
          return unknown (false);
     }    
  case DOCUMENT_NODE:
     return documentElement.isDefaultNamespace(namespaceURI);
  case ENTITY_NODE:
  case NOTATION_NODE:
  case DOCUMENT_TYPE_NODE:
  case DOCUMENT_FRAGMENT_NODE:
     return unknown (false);
  case ATTRIBUTE_NODE:
     if ( Attr has an owner Element )
     {          
          return ownerElement.isDefaultNamespace(namespaceURI);
     }
     else {
          return unknown (false);
     }    
  default:
     if ( Node has an ancestor Element )
         // EntityReferences may have to be skipped to get to it
     {          
          return ancestorElement.isDefaultNamespace(namespaceURI);
     }
     else {
          return unknown (false);
     }    
  }
}