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Section 12--Automatic loading of classes--ClassesandObjectsinPHP512_PHP tutorial
- WBOYOriginal
- 2016-07-13 17:24:08809browse
| = This article is read by Haohappy > | = Notes from the Chapter Classes and Objects | = Translation + personal experience | = Please do not reprint to avoid unnecessary trouble that may occur, thank you | = Welcome to criticize and correct me, Hope to make progress together with all PHP enthusiasts! +------------------------------------------------ ---------------------------------------+ */ Section 12--Class Autoloading PHP will report a fatal error when you try to use an undefined class. The solution is to add a class, which can be included in a file. After all, you know which class to use. However, PHP provides a class Autoloading function, which can save programming time. When you try to use a class that PHP has not organized into, it will look for a global function __autoload. If this function exists, PHP will call it with a parameter, which is the class name. Example 6.15 illustrates how __autoload is used. It assumes that each file in the current directory corresponds to a class. When the script attempts to generate an instance of class User, PHP will execute __autoload. The script assumes that class_User.php defines There is a User class. Regardless of whether the call is in uppercase or lowercase, PHP will return the lowercase version of the name. Listing 6.15 Class autoloading name = "Leon"; $u->printName(); ?>