This function returns a new instance of class DOMAttr. The name of the attribute is the value of the first parameter. Este nodo no sera mostrado en el documento a no ser que sea introducido por ejemplo con DOMNode->appendChild().
The return value is FALSE if an error occurred.
See also DOMDocument->createElement(), DOMNode->appendChild(), DOMDocument->createTextNode(), DOMDocument->createComment() and DOMDocument->createProcessingInstruction().