SimpleXMLElement::__construct
(PHP 5 >= 5.0.1)
SimpleXMLElement::__construct — Creates a new SimpleXMLElement object
Descrição
Creates a new SimpleXMLElement object.
Parâmetros
- 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
-
Namespace prefix or URI.
- is_prefix
-
TRUE if ns is a prefix, FALSE if it's a URI; defaults to FALSE.
Valor Retornado
Returns a SimpleXMLElement object representing data.
Erros
Produces an E_WARNING error message for each error found in the XML data and additionally throws an exception if the XML data could not be parsed.
Use libxml_use_internal_errors() to suppress all XML errors, and libxml_get_errors() to iterate over them afterwards.
Exemplos
Nota:
Listed examples may include example.php, which refers to the XML string found in the first example of the basic usage guide.
Exemplo #1 Create a SimpleXMLElement object
<?php
include 'example.php';
$sxe = new SimpleXMLElement($xmlstr);
echo $sxe->movie[0]->title;
?>O exemplo acima irá imprimir:
PHP: Behind the Parser
Exemplo #2 Create a SimpleXMLElement object from a URL
<?php
$sxe = new SimpleXMLElement('http://example.org/document.xml', NULL, TRUE);
echo $sxe->asXML();
?>Veja Também
- Basic usage
- simplexml_load_string() - Transforma uma string XML em objeto
- simplexml_load_file() - Converte um arquivo XML em um objeto
- Dealing with XML errors
- libxml_use_internal_errors() - Desabilita erros da libxml e permite que o usuário obtenha informação do erro como necessitar
User Contributed Notes
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();
}
?>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", $response);
?>As I was filling out a bug report, I realized why (speculation here) the constructor is final: so that functions like simplexml_load_file and simplexml_load_string can work. I imagine the PHP-ized code looks something like
<?php
function simplexml_load_file($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.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 :-?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.