PHP Iterator迭代对象AG接口 bbin接口对接网站平台方法

AG接口 bbin接口对接网站平台方法Q-用2947702644法和之前的数组遍历是一样的，只不过这里遍历的key是属性名，value是属性值。在类外部遍历时，只能遍历到public属性的，因为其它的都是受保护的，类外部不可见。

class HardDiskDrive {

public $brand;
public $color;
public $cpu;
public $workState;

protected $memory;
protected $hardDisk;

private $price;

public function __construct($brand, $color, $cpu, $workState, $memory, $hardDisk, $price) {

    $this->brand = $brand;
    $this->color = $color;
    $this->cpu   = $cpu;
    $this->workState = $workState;
    $this->memory = $memory;
    $this->hardDisk = $hardDisk;
    $this->price = $price;
}

}

$hardDiskDrive = new HardDiskDrive('希捷', 'silver', 'tencent', 'well', '1T', 'hard', '$456');

foreach ($hardDiskDrive as $property => $value) {

var_dump($property, $value);
echo '<br>';

}
输出结果为:

string(5) "brand" string(6) "希捷"
string(5) "color" string(6) "silver"
string(3) "cpu" string(7) "tencent"
string(9) "workState" string(4) "well"
通过输出结果我们也可以看得出来常规遍历是无法访问受保护的属性的。
如果我们想遍历出对象的所有属性，就需要控制foreach的行为，就需要给类对象，提供更多的功能，需要继承自Iterator的接口:

class Team implements Iterator {

//private $name = 'itbsl';
//private $age  = 25;
//private $hobby = 'fishing';

private $info = ['itbsl', 25, 'fishing'];

public function rewind()
{
    reset($this->info); //重置数组指针
}

public function valid()
{
    //如果为null,表示没有元素，返回false
    //如果不为null,返回true

    return !is_null(key($this->info));
}

public function current()
{
    return current($this->info);
}

public function key()
{
    return key($this->info);
}

public function next()
{
    return next($this->info);
}

}

$team = new Team();

foreach ($team as $property => $value) {

var_dump($property, $value);
echo '<br>';

}