PHP: Whats's the difference between the SimpleXMLElement() class and SimpleXML_load_string()?

VicePrez picture VicePrez · May 20, 2011 · Viewed 7.3k times · Source

I've seen alot of coders implement SimpleXML_load_string() instead of the SimpleXMLElement() class. Are there any benefits to using the former over the latter? I've read the PHP manual on simplexml. I couldn't manage to get a grasp on what it is.

Any help and guidance (perhaps through examples) would be much appreciated. Thanks in advance.

Answer

KingCrunch picture KingCrunch · May 20, 2011

simplexml_load_string() (as the name suggest) load xml from a string and returns an object of SimepleXMLElement. There is no difference between this and using just the usual constructor of the class.

Update:

SimpleXML::__construct() has an additional parameter (the third one) bool $data_is_url = false. If this is true the behavior is the same as simplexml_load_file() (in conjunction with the common stream wrappers). Thus both simplexml_load_*()-functions cover the same functionality as SimpleXML::__construct().

Additional the functions simplexml_load_*() has a second parameter string $class_name = "SimpleXMLElement" to specify the class of the object to get returned. Thats not a specific feature of the functions, because you can "use" something very similar with usual instanciation too

class MyXML extends SimpleXMLElement {}
$a = new MyXML($xml);
$b = simplexml_load_string($xml, 'MyXML');

A difference between the OOP- and the procedural approach is, that the functions return false on error, but the constructor throws an Exception.