Php/docs/function.libxml-set-external-entity-loader
libxml_set_external_entity_loader
(PHP 5 >= 5.4.0, PHP 7)
libxml_set_external_entity_loader — Changes the default external entity loader
说明
libxml_set_external_entity_loader
( callable|null $resolver_function
) : bool
Changes the default external entity loader.
参数
resolver_function- A callable that takes three arguments. Two strings, a public id and system id, and a context (an array with four keys) as the third argument. This callback should return a resource, a string from which a resource can be opened, or
null.
返回值
成功时返回 true， 或者在失败时返回 false。
范例
Example #1 libxml_set_external_entity_loader() example
<?php$xml = <<<XML<!DOCTYPE foo PUBLIC "-//FOO/BAR" "http://example.com/foobar%22><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());?>
以上例程会输出：
string(10) "-//FOO/BAR"
string(25) "http://example.com/foobar"
array(4) {
["directory"] => NULL
["intSubName"] => NULL
["extSubURI"] => NULL
["extSubSystem"] => NULL
}
bool(true)
