各种类及接口

The ArrayObject class

(PHP 5, PHP 7)

This class allows objects to work as arrays.

类摘要

ArrayObject implements IteratorAggregate , ArrayAccess , Serializable , Countable
{
	/* 常量 */
	const integer STD_PROP_LIST = 1 ;
	const integer ARRAY_AS_PROPS = 2 ;
	/* 方法 */
	public __construct ([ mixed $input = array() [, int $flags = 0 [, string $iterator_class = "ArrayIterator" ]]] )
	public append ( mixed $value ) : void
	public asort ( void ) : void
	public count ( void ) : int
	public exchangeArray ( mixed $input ) : array
	public getArrayCopy ( void ) : array
	public getFlags ( void ) : int
	public getIterator ( void ) : ArrayIterator
	public getIteratorClass ( void ) : string
	public ksort ( void ) : void
	public natcasesort ( void ) : void
	public natsort ( void ) : void
	public offsetExists ( mixed $index ) : bool
	public offsetGet ( mixed $index ) : mixed
	public offsetSet ( mixed $index , mixed $newval ) : void
	public offsetUnset ( mixed $index ) : void
	public serialize ( void ) : string
	public setFlags ( int $flags ) : void
	public setIteratorClass ( string $iterator_class ) : void
	public uasort ( callable $cmp_function ) : void
	public uksort ( callable $cmp_function ) : void
	public unserialize ( string $serialized ) : void
}

As you know ArrayObject is not an array so you can't use the built in array functions. Here's a trick around that:
Extend the ArrayObject class with your own and implement this magic method:
<?php
    public function __call($func, $argv)
    {
        if (!is_callable($func) || substr($func, 0, 6) !== 'array_')
        {
            throw new BadMethodCallException(__CLASS__.'->'.$func);
        }
        return call_user_func_array($func, array_merge(array($this->getArrayCopy()), $argv));
    }
?>
Now you can do this with any array_* function:
<?php
$yourObject->array_keys();
?>
- Don't forget to ommit the first parameter - it's automatic!
Note: You might want to write your own functions if you're working with large sets of data.

The SplObserver interface

(PHP 5 >= 5.1.0, PHP 7)

The SplObserver interface is used alongside SplSubject to implement the Observer Design Pattern.

类摘要

SplObserver
{
	/* 方法 */
	abstract public update ( SplSubject $subject ) : void
}

<?php
/**
* Subject,that who makes news
*/
class Newspaper implements \SplSubject{
    private $name;
    private $observers = array();
    private $content;
   
    public function __construct($name) {
        $this->name = $name;
    }
    //add observer
    public function attach(\SplObserver $observer) {
        $this->observers[] = $observer;
    }
   
    //remove observer
    public function detach(\SplObserver $observer) {
       
        $key = array_search($observer,$this->observers, true);
        if($key){
            unset($this->observers[$key]);
        }
    }
   
    //set breakouts news
    public function breakOutNews($content) {
        $this->content = $content;
        $this->notify();
    }
   
    public function getContent() {
        return $this->content." ({$this->name})";
    }
   
    //notify observers(or some of them)
    public function notify() {
        foreach ($this->observers as $value) {
            $value->update($this);
        }
    }
}
/**
* Observer,that who recieves news
*/
class Reader implements SplObserver{
    private $name;
   
    public function __construct($name) {
        $this->name = $name;
    }
   
    public function update(\SplSubject $subject) {
        echo $this->name.' is reading breakout news '.$subject->getContent().'
';
    }
}
$newspaper = new Newspaper('Newyork Times');
$allen = new Reader('Allen');
$jim = new Reader('Jim');
$linda = new Reader('Linda');
//add reader
$newspaper->attach($allen);
$newspaper->attach($jim);
$newspaper->attach($linda);
//remove reader
$newspaper->detach($linda);
//set break outs
$newspaper->breakOutNews('USA break down!');
//=====output======
//Allen is reading breakout news USA break down! (Newyork Times)
//Jim is reading breakout news USA break down! (Newyork Times)

The SplSubject interface

(PHP 5 >= 5.1.0, PHP 7)

The SplSubject interface is used alongside SplObserver to implement the Observer Design Pattern.

类摘要

SplSubject 
{
	/* 方法 */
	abstract public attach ( SplObserver $observer ) : void
	abstract public detach ( SplObserver $observer ) : void
	abstract public notify ( void ) : void
}

<?php
// Example implementation of Observer design pattern:
class MyObserver1 implements SplObserver {
    public function update(SplSubject $subject) {
        echo __CLASS__ . ' - ' . $subject->getName();
    }
}
class MyObserver2 implements SplObserver {
    public function update(SplSubject $subject) {
        echo __CLASS__ . ' - ' . $subject->getName();
    }
}
class MySubject implements SplSubject {
    private $_observers;
    private $_name;
    public function __construct($name) {
        $this->_observers = new SplObjectStorage();
        $this->_name = $name;
    }
    public function attach(SplObserver $observer) {
        $this->_observers->attach($observer);
    }
    public function detach(SplObserver $observer) {
        $this->_observers->detach($observer);
    }
    public function notify() {
        foreach ($this->_observers as $observer) {
            $observer->update($this);
        }
    }
    public function getName() {
        return $this->_name;
    }
}
$observer1 = new MyObserver1();
$observer2 = new MyObserver2();
$subject = new MySubject("test");
$subject->attach($observer1);
$subject->attach($observer2);
$subject->notify();
/*
will output:
MyObserver1 - test
MyObserver2 - test
*/
$subject->detach($observer2);
$subject->notify();
/*
will output:
MyObserver1 - test
*/
?>