SimpleXMLElement::children
As I was filling out a bug report, I realized why (speculation here) the constructor is final: so that functions like simplexml_load_file and simplexml_load_string can work. I imagine the PHP-ized code looks something like
<?php
function simplexml_load_file($filename, $class_name = "SimpleXMLElement", $options = 0, $ns = "", $is_prefix = false) {
return new $class_name($filename, $options, true, $ns, $is_prefix);
}
?>
If we were to use a different $class_name and change the constructor's definition these functions wouldn't work.
There's no easy, sensible solution that keeps simplexml_load_file and simplexml_load_string.
SimpleXMLElement::__construct
(PHP 5 >= 5.0.1)
SimpleXMLElement::__construct — Creates a new SimpleXMLElement object
Description
SimpleXMLElement
__construct
( string $data
[, int $options
[, bool $data_is_url
[, string $ns
[, bool $is_prefix
]]]] )
Creates a new SimpleXMLElement object.
Parameters
- data
-
A well-formed XML string or the path or URL to an XML document if data_is_url is TRUE.
- options
-
Optionally used to specify additional Libxml parameters.
- data_is_url
-
By default, data_is_url is FALSE. Use TRUE to specify that data is a path or URL to an XML document instead of string data.
- ns
-
- is_prefix
-
Return Values
Returns a SimpleXMLElement object representing data .
Errors/Exceptions
Produces an E_WARNING error message for each error found in the XML data and throws an exception if errors were detected.
Tip
Use libxml_use_internal_errors() to suppress all XML errors, and libxml_get_errors() to iterate over them afterwards.
Examples
Example #1 Create a SimpleXMLElement object
<?php
include 'example.php';
$sxe = new SimpleXMLElement($xmlstr);
echo $sxe->movie[0]->title;
?>
Example #2 Create a SimpleXMLElement object from a URL
<?php
$sxe = new SimpleXMLElement('http://example.org/document.xml', NULL, TRUE);
echo $sxe->asXML();
?>
See Also
- simplexml_load_string() - Interprets a string of XML into an object
- simplexml_load_file() - Interprets an XML file into an object
- Dealing with XML errors
- libxml_use_internal_errors() - Disable libxml errors and allow user to fetch error information as needed
add a note
User Contributed NotesSimpleXMLElement::__construct
uramihsayibok, gmail, com
17-Aug-2009 03:52
17-Aug-2009 03:52
jmshinn at gmail dot com
07-Nov-2008 12:12
07-Nov-2008 12:12
Note to tudor:
You can't override the constructor, but you can get around that with a simple static method:
<?php
class simpleXmlExtender extends SimpleXMLElement {
public static function _new($xml=NULL, $ns=NULL, $prefix=TRUE) {
// allows you to set certain option parameters to new default values,
// or automatically decide whether input data is a file or not
// optionally, you can save the object in an intermediate variable
// and peform other actions on/with it before returning it
return new simpleXmlExtender($xml, LIBXML_NOCDATA, file_exists($xml), $ns, $prefix);
}
}
$simpleXML = simpleXmlExtender::_new($xmldata);
?>
... it's a bit of a hack, but it works.
alvaro at demogracia dot com
30-Sep-2008 10:42
30-Sep-2008 10:42
A note about the undocumented parameters:
$ns (string): namespace prefix or URI
$is_prefix (bool): TRUE if $ns is a prefix, FALSE if it's a URI; defaults to FALSE
E.g.:
<?php
$xml_string = '<xml xmlns:foo='uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882'>
<foo:bar>..................';
$a = new SimpleXMLElement($xml_string, NULL, FALSE, 'foo', TRUE);
$b = new SimpleXMLElement($xml_string, NULL, FALSE, 'uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882', FALSE);
?>
However, I don't know exactly what these parameters are used for. They don't seem to be of much help when dealing with namespaces :-?
tudor at culise dot net
20-Nov-2007 12:35
20-Nov-2007 12:35
This class is extendable, but it's too bad that its constructor cannot be overriden (PHP says it's a final method). Thus the class should be wrapped using the delegation principle rather that extended.