spl_autoload_register
(PHP 5 >= 5.1.2, PHP 7)
spl_autoload_register — Register given function as __autoload() implementation
Description
bool spl_autoload_register ([ callable $autoload_function [, bool $throw = true [, bool $prepend = false ]]] )Register a function with the spl provided __autoload queue. If the queue is not yet activated it will be activated.
If your code has an existing __autoload() function then this function must be explicitly registered on the __autoload queue. This is because spl_autoload_register() will effectively replace the engine cache for the __autoload() function by either spl_autoload() or spl_autoload_call().
If there must be multiple autoload functions, spl_autoload_register() allows for this. It effectively creates a queue of autoload functions, and runs through each of them in the order they are defined. By contrast, __autoload() may only be defined once.
Parameters
autoload_function
The autoload function being registered. If no parameter is provided, then the default implementation of spl_autoload() will be registered.
throw
This parameter specifies whether spl_autoload_register() should throw exceptions when the autoload_function cannot be registered.
prepend
If true, spl_autoload_register() will prepend the autoloader on the autoload queue instead of appending it.
Return Values
Returns TRUE on success or FALSE on failure.
Changelog
Version | Description |
|---|---|
5.3.0 | Namespaces support was introduced. |
5.3.0 | The prepend parameter was added. |
Examples
Example #1 spl_autoload_register() as a replacement for an __autoload() function
<?php
//?function?__autoload($class)?{
//?????include?'classes/'?.?$class?.?'.class.php';
//?}
function?my_autoloader($class)?{
????include?'classes/'?.?$class?.?'.class.php';
}
spl_autoload_register('my_autoloader');
//?Or,?using?an?anonymous?function?as?of?PHP?5.3.0
spl_autoload_register(function?($class)?{
????include?'classes/'?.?$class?.?'.class.php';
});
?>Example #2 spl_autoload_register() example where the class is not loaded
<?php
namespace?Foobar;
class?Foo?{
????static?public?function?test($name)?{
????????print?'[['.?$name?.']]';
????}
}
spl_autoload_register(__NAMESPACE__?.'\Foo::test');?//?As?of?PHP?5.3.0
new?InexistentClass;
?>The above example will output something similar to:
[[Foobar\InexistentClass]]
Fatal error: Class 'Foobar\InexistentClass' not found in ...See Also
- __autoload() - Attempt to load undefined class
← spl_autoload_functions
spl_autoload_unregister →
? 1997–2017 The PHP Documentation GroupLicensed under the Creative Commons Attribution License v3.0 or later.
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