Note:
Prior to PHP 5.3, exceptions thrown in the __autoload() function could not be caught in the catch block and would result in a fatal error. From PHP 5.3 and upwards, this is possible provided that if a custom exception is thrown, then the custom exception class is available. The __autoload() function may be used recursively to autoload the custom exception class.
Note:
Autoloading is not available if using PHP in CLI interactive mode.
Note:
If the class name is used e.g. in call_user_func() then it can contain some dangerous characters such as ../. It is recommended to not use the user-input in such functions or at least verify the input in __autoload().
This example attempts to load the classes MyClass1 and MyClass2 from the files MyClass1.php and MyClass2.php respectively.
<?php spl_autoload_register(function ($class_name) { include $class_name . '.php'; }); $obj = new MyClass1(); $obj2 = new MyClass2(); ?>
This example attempts to load the interface ITest.
<?php spl_autoload_register(function ($name) { var_dump($name); }); class Foo implements ITest { } /* string(5) "ITest" Fatal error: Interface 'ITest' not found in ... */ ?>
This example throws an exception and demonstrates the try/catch block.
<?php spl_autoload_register(function ($name) { echo "Want to load $name.\n"; throw new Exception("Unable to load $name."); }); try { $obj = new NonLoadableClass(); } catch (Exception $e) { echo $e->getMessage(), "\n"; } ?>
The above example will output:
Want to load NonLoadableClass. Unable to load NonLoadableClass.
This example throws an exception for a non-loadable, custom exception.
<?php spl_autoload_register(function ($name) { echo "Want to load $name.\n"; throw new MissingException("Unable to load $name."); }); try { $obj = new NonLoadableClass(); } catch (Exception $e) { echo $e->getMessage(), "\n"; } ?>
The above example will output:
Want to load NonLoadableClass. Want to load MissingException. Fatal error: Class 'MissingException' not found in testMissingException.php on line 4
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