SimpleXMLElement::__construct

(PHP 5 >= 5.0.1)

SimpleXMLElement::__construct Cria um novo objeto SimpleXMLElement

Descrição

SimpleXMLElement
__construct ( string $data [, int $options [, bool $data_is_url [, string $ns [, bool $is_prefix ]]]] )

Cria um novo objeto SimpleXMLElement.

Parâmetros

data

Uma string XML bem formada ou um caminho ou URL para um documento XML se data_is_url é TRUE.

options

Opcionalmente usado para especificar parâmetros adicionais Libxml.

data_is_url

Por padrão, data_is_url é FALSE. Use TRUE para especificar que data é um caminho ou URL para um documento XML ao invés de string.

ns

is_prefix

Valor Retornado

Retorna um objeto SimpleXMLElement representando data .

Erros

Produz uma mensagem de erro E_WARNING para cada erro encontrado nos dados do XML e dispara uma exceção se os erros foram detectados.

Exemplos

Exemplo #1 Cria um objeto SimpleXMLElement

<?php

include 'example.php';

$sxe = new SimpleXMLElement($xmlstr);
echo 
$sxe->movie[0]->title;

?>

Exemplo #2 Cria um objeto SimpleXMLElement de uma URL

<?php

$sxe 
= new SimpleXMLElement('http://example.org/document.xml'NULLTRUE);
echo 
$sxe->asXML();

?>



User Contributed Notes
SimpleXMLElement::__construct
uramihsayibok, gmail, com
16-Aug-2009 10:52
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.
jmshinn at gmail dot com
06-Nov-2008 09:12
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 05:42
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 09:35
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.