Last updated: Fri, 20 May 2011

SimpleXMLElement::__construct

(PHP 5 >= 5.0.1)

SimpleXMLElement::__construct — Crea un nuevo objeto SimpleXMLElement

Descripción

public SimpleXMLElement::__construct() ( string $data [, int $options = 0 [, bool $data_is_url = false [, string $ns = "" [, bool $is_prefix = false ]]]] )

Crea un nuevo objeto SimpleXMLElement.

Parámetros

data: Un string XML correcto o la ruta o URL a un documento XML si data_is_url es TRUE.
options: Usado para especificar additionalLibxml parameters opcionales.
data_is_url: Por defecto, data_is_url es FALSE. Usar TRUE para precisar que data es una ruta o URL a un documento XML en vez de un string de datos.
ns
is_prefix

Valores devueltos

Retorna un objeto SimpleXMLElement representando data.

Errores/Excepciones

Produce un mensaje de error E_WARNING por cada error encontrado en los datos XML y lanza una excepcion si se han detectado errores.

Tip

Debe usarse libxml_use_internal_errors() para eliminar todos los errores XML y libxml_get_errors() para iterar sobre ellos después.

Ejemplos

Note:
Los ejemplos listados quizá incluyen example.php, que hacen referencia a la cadena XML encontrada en el primer ejemplo de la guía de uso básico.

Example #1 Crea un objeto SimpleXMLElement


<?php

include 'example.php';

$sxe = new SimpleXMLElement($xmlstr);
echo $sxe->pelicula[0]->titulo;

?>

El resultado del ejemplo sería:

PHP: Tras el Parser

Example #2 Crea un objeto SimpleXMLElement a partir de una URL


<?php

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

?>

Ver también

simplexml_load_string() - Interpreta un string de XML en un objeto
simplexml_load_file() - Interpreta un fichero XML en un objeto
Lidiar con los errores XML
libxml_use_internal_errors() - Deshabilita errores libxml y permite al usuario extraer información de errores según sea necesario

SimpleXMLElement::count

SimpleXMLElement::children

Last updated: Fri, 20 May 2011

add a note User Contributed Notes SimpleXMLElement::__construct

kumarldh at gmail dot com 23-Mar-2011 06:50


Using libxml_use_internal_errors() may suppress errors but Exception still requires decent handling. I used following code snippet.





<?php


libxml_use_internal_errors(true);


try{


    $xmlToObject = new SimpleXMLElement($notSoWellFormedXML);


} catch (Exception $e){


    echo 'Please try again later...';


    exit();


}


?>

zwilson at gulosolutions dot com 19-Nov-2009 06:16


SimpleXML does not correctly parse SOAP XML results if the result comes back with colons ‘:’ in a tag, like <soap:Envelope>. Why? Because SimpleXML treats the colon character ‘:’ as an XML namespace, and places the entire contents of the SOAP XML result inside a namespace within the SimpleXML object. There is no real way to correct this using SimpleXML, but we can alter the raw XML result a little before we send it to SimpleXML to parse.





All we have to do is use the preg_replace function to get rid of the colons in the SOAP response tags BEFORE you hand it off to SimpleXML, like so:





<?php


// SimpleXML seems to have problems with the colon ":" in the <xxx:yyy> response tags, so take them out


$xmlString = preg_replace("/(<\/?)(\w+):([^>]*>)/", "$1$2$3", $response);


?>

uramihsayibok, gmail, com 17-Aug-2009 01:52


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.

alvaro at demogracia dot com 30-Sep-2008 08:42


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 11:35


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.

add a note