Spl_autoload_register () and _ autoload (), splregisterautoload

Spl_autoload_register () and _ autoload (), splregisterautoload

About spl_autoload_register () and _ autoload ()

See the usage of the two:

 

// _ Autoload usage function _ autoload ($ classname) {$ filename = ". /class /". $ classname. ". class. php "; if (is_file ($ filename) {include $ filename ;}}
// Spl_autoload_register usage spl_autoload_register ('Load _ class ');
Function load_class ($ classname) {$ filename = ". /class /". $ classname. ". class. php "; if (is_file ($ filename) {include $ filename ;}}

 

The advantage of using spl_autoload_register () is that (1) it is more convenient to automatically load objects. Many frameworks do this:

Class ClassAutoloader {public function _ construct () {spl_autoload_register (array ($ this, 'loader ');} private function loader ($ className) {echo 'trying to load ', $ className, 'via', _ METHOD __, "() \ n"; include $ className. '. php ';}}
$ Autoloader = new ClassAutoloader ();
$ Obj = new Class1 (); $ obj = new Class2 ();

 

(2) You must know that the _ autoload () function can only exist once. Of course, spl_autoload_register () can register multiple functions.

 

Function a () {include 'a. php';} function B () {include 'B. php';} spl_autoload_register ('A'); spl_autoload_register (' B ');

 

(3) SPL functions are rich and provide more functions, such as spl_autoload_unregister () to deregister registered functions, spl_autoload_functions () to return all registered functions.