### PHP 中的类－操作 XML(3)

/* Here are the XML functions needed by expat */
/* when expat hits an opening tag, it fires up this function */
function startElement($parser, $name, $attrs) {
array_push($this->current_tag, $name); // add tag to the cur. tag array
$curtag = implode("_",$this->current_tag); // piece together tag
/* this tracks what array index we are on for this tag */
if(isset($this->tagtracker["$curtag"])) {
$this->tagtracker["$curtag"]++;
} else {
$this->tagtracker["$curtag"]=0;
}
/* if there are attributes for this tag, we set them here. */
if(count($attrs)>0) {
$j = $this->tagtracker["$curtag"];
if(!$j) $j = 0;
if(!is_object($GLOBALS[$this->identifier]["$curtag"][$j])) {
$GLOBALS[$this->identifier]["$curtag"][$j] = new xml_container;
}
$GLOBALS[$this->identifier]["$curtag"][$j]->store("attributes",$attrs);
}
} // end function startElement
/* when expat hits a closing tag, it fires up this function */
function endElement($parser, $name) {
$curtag = implode("_",$this->current_tag); // piece together tag
// before we pop it off,
// so we can get the correct
// cdata
if(!$this->tagdata["$curtag"]) {
$popped = array_pop($this->current_tag); // or else we screw up where we are
return; // if we have no data for the tag
} else {
$TD = $this->tagdata["$curtag"];
unset($this->tagdata["$curtag"]);
}
$popped = array_pop($this->current_tag);
// we want the tag name for
// the tag above this, it
// allows us to group the
// tags together in a more
// intuitive way.
if(sizeof($this->current_tag) == 0) return; // if we aren't in a tag
$curtag = implode("_",$this->current_tag); // piece together tag
// this time for the arrays
$j = $this->tagtracker["$curtag"];
if(!$j) $j = 0;
if(!is_object($GLOBALS[$this->identifier]["$curtag"][$j])) {
$GLOBALS[$this->identifier]["$curtag"][$j] = new xml_container;
}
$GLOBALS[$this->identifier]["$curtag"][$j]->store($name,$TD); #$this->tagdata["$curtag"]);
unset($TD);
return TRUE;
}
/* when expat finds some internal tag character data,
it fires up this function */
function characterData($parser, $cdata) {
$curtag = implode("_",$this->current_tag); // piece together tag
$this->tagdata["$curtag"] .= $cdata;
}
/* this is the constructor: automatically called when the class is initialized */
function xml($data,$identifier='xml') {
$this->identifier = $identifier;
// create parser object
$this->xml_parser = xml_parser_create();
// set up some options and handlers
xml_set_object($this->xml_parser,$this);
xml_parser_set_option($this->xml_parser,XML_OPTION_CASE_FOLDING,0);
xml_set_element_handler($this->xml_parser, "startElement", "endElement");
xml_set_character_data_handler($this->xml_parser, "characterData");
if (!xml_parse($this->xml_parser, $data, TRUE)) {
sprintf("XML error: %s at line %d",
xml_error_string(xml_get_error_code($this->xml_parser)),
xml_get_current_line_number($this->xml_parser));
}
// we are done with the parser, so let's free it
xml_parser_free($this->xml_parser);

} // end constructor: function xml()
} // thus, we end our class xml
?>