Spl--spl_autoload_register

Spl_autoload_register () :

When a class is called Undefined, all functions registered to the Spl_autoload_register () function are called sequentially, instead of calling the __autoload function.

solve the problem :

The function __autoload ($classname) can be dynamically loaded classes, avoiding the use of require_once statements, but if you have a large-scale application that contains libraries or smaller applications, each application may want to declare a __ The AutoLoad function to find his file. The problem is that declaring two __autoload () functions at the global scope produces a duplicate declaration error.

Usage:

The SPL function accepts 3 parameters: [Add to the function of the auto-load stack, the loader cannot find the flag of the class when the exception is thrown = True, register to the team header instead of the end of the queue = false]

The first parameter is optional, which, by default, points to Spl_autoload (), which automatically finds files in the path that have a lowercase class name and a. php or. ini extension, or other extensions that are registered to the Spl_autoload_extensions () function.

<?PHPDefine(' Class_dir ', ' class/')/** Set_include_path Set the path of the PHP include file * Get_include_path gets the path of the current PHP include file, default.:/ usr/share/pear:/usr/share/php//linux to: Split, win with; split * Path_separator constant, which represents the delimiter of the current system*/Set_include_path(Get_include_path(). Path_separator. CLASS_DIR);//extension PHP contains file path//registration and returns the default file name extension used by the Spl_autoload function, this function is used to modify and examine the __autoload () function built-in default implementation function Spl_autoload () used by the extension, the default Spl_ The AutoLoad function uses a ". inc,.php" extension.   Spl_autoload_extensions ('. Class.php,inc,interface,.class '); Register multipleSpl_autoload_extensions ('. class.php '));//Default method//spl_autoload_register ();//Default Call, exception thrown by defaultSpl_autoload_register (NULL,false);//with default function, no exception is thrown when class is not foundSpl_autoload_register (' MyLoader1 ',false); Spl_autoload_register (' MyLoader2 ',false);//when instantiating a class, Spl_autoload () looks in the containing path first, where the class/ Test.class.php exists, will be include, if not present, will call myloader1,2 custom function, if still not found, throw a class exception that is not correctly declared. $instance=NewTest ();

Secure Call:

Once the Spl_autoload_register () is called, the __autoload () function in the program is not called back, and if you want to preserve the function of the __autoload (), register it as the first function in the auto-load stack:

if false = = = spl_autoload_function ()    ) {iffunction_exists(' __autoload ')) {        Spl_autoload_register (false);    }}

Spl_autoload_function (): Returns an array of registered functions and returns False if the SPL auto-load stack has not been initialized.

Spl--spl_autoload_register