Quick Reference
The PHP libxml_set_external_entity_loader() function changes the default external entity loader.
<?php
$xml = <<<XML
<!DOCTYPE foo PUBLIC '-//FOO/BAR" "http://example.com/'>
<foo>bar</foo>
XML;
$dtd = <<<DTD
<!ELEMENT foo (#PCDATA)>
DTD;
libxml_set_external_entity_loader(
function ($public, $system, $context) use($dtd) {
var_dump($public);
var_dump($system);
var_dump($context);
$f = fopen('php://temp', 'r+');
fwrite($f, $dtd);
rewind($f);
return $f;
}
);
$dd = new DOMDocument;
$r = $dd->loadXML($xml);
var_dump($dd->validate());
?>Syntax
libxml_set_external_entity_loader(function)Parameters
| Parameter | Description |
|---|---|
| function | A function that takes three arguments: two strings, a public id and system id, and a context (an array with four keys) as the third argument; this callback should return a resource, a string from which a resource can be opened, or NULL (required) |
PHP Notes:
- When using PHP, single or double quotation marks are acceptable and work identically to one another; choose whichever you prefer, and stay consistent
- Arrays count starting from zero NOT one; so item 1 is position [0], item 2 is position [1], and item 3 is position [2] … and so on
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