Many developers writing object-oriented applications create
one PHP source file per-class definition. One of the biggest
annoyances is having to write a long list of needed includes
at the beginning of each script (one for each class).
In PHP 5, this is no longer necessary. You may define an
__autoload function which is automatically
called in case you are trying to use a class which hasn't been
defined yet. By calling this function the scripting engine is given
a last chance to load the class before PHP fails with an error.
Note:
Exceptions thrown in __autoload function cannot be caught in the
catch block and results in
a fatal error.
Example 19-5. Autoload example
This example attempts to load the classes MyClass1
and MyClass2 from the files MyClass1.php
and MyClass2.php respectively.
<?php
function __autoload($class_name) {
require_once $class_name . '.php';
}
$obj = new MyClass1();
$obj2 = new MyClass2();
?>
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