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PHP example tutorial PHP automatic loading class usage example analysis

Jul 28, 2016 am 08:28 AM

The example in this article describes the usage of PHP automatic loading class. Share it with everyone for your reference, the details are as follows:

<?php
//function __autoload($class_name) {
//  require_once $class_name . '.php';
//}
spl_autoload_register(array("core",'autoload'));//当实例化类的时候,自动调用core类中的autoload()方法来载入类
//也可以使用__autoload()来实现,但是php新版本建议使用spl_autoload_register,因为__autoload()会被逐渐废弃掉
$obj = new MyClass1();
$obj2 = new MyClass2();
class core
{
  public static function autoload($class) {
    require $class.'.php';
  }
}

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Understanding the idea is the most important thing:

Automatic loading of objects

Many developers create a PHP source file for the definition of each class when writing object-oriented applications . A big annoyance is having to write a long list of include files (one file per class) at the beginning of each script.

In PHP 5, this is no longer necessary. It is possible to define an __autoload() function that is automatically called when an attempt is made to use a class that has not yet been defined. By calling this function, the scripting engine has a last chance to load the required classes before PHP fails with an error.

Tip

spl_autoload_register() provides a more flexible way to implement automatic loading of classes. Therefore, use of the __autoload() function is no longer recommended and may be deprecated in a future version.

Readers who are interested in more PHP-related content can check out the special topics of this site: "Introduction Tutorial on PHP Object-Oriented Programming", "Summary of PHP Mathematical Operation Skills", "Summary of PHP Office Document Skills (including word, excel, access) , ppt)", "Complete PHP Array (Array) Operation Skills", "PHP Data Structure and Algorithm Tutorial", "php Programming Algorithm Summary", "php Regular Expression Usage Summary", and "php Common Database Operation Skills Summary" 》

I hope this article will be helpful to everyone in PHP programming.

The above introduces the PHP example tutorial and the PHP automatic loading class usage example analysis, including the content of the PHP example tutorial. I hope it will be helpful to friends who are interested in PHP tutorials.

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