(PHP 5, PHP 7)
DOMElement::hasAttributeNS — Checks to see if attribute exists
$namespaceURI
   , string $localName
   )
   Indicates whether attribute in namespace namespaceURI 
   named localName exists as a member of the element.
  
namespaceURIThe namespace URI.
localNameThe local name.
   Returns TRUE on success or FALSE on failure.