PHP。 是否可以将array_column与对象数组一起使用

Question

Is it possible to pass in array_column an array of objects?
I have implemented ArrayAccess interface, but it has no effect.
Should I implement another one?

class Foo implements ArrayAccess {

    public $Id, $Title;

    public function offsetExists($offset)
    {
        return isset($this->{$offset});
    }    

    public function offsetGet($offset)
    {
        return $this->{$offset};
    }

    public function offsetSet($offset, $value)
    {
        $this->{$offset} = $value;
    }

    public function offsetUnset($offset)
    {
        unset($this->{$offset});
    }
}

$object = new \Foo();
$object->Id = 1;
$object->Title = 'Test';

$records = array(
    $object, 
    array(
        'Id' => 2,
        'Title' => 'John'
    )
);

var_dump(array_column($records, 'Title')); // array (size=1) 0 => string 'John' (length=4)

Answer 1

PHP 5

array_column doesn't work with an array of objects. Use array_map instead:

$titles = array_map(function($e) {
    return is_object($e) ? $e->Title : $e['Title'];
}, $records);

PHP 7

array_column()

The function now supports an array of objects as well as two-dimensional arrays. Only public properties are considered, and objects that make use of __get() for dynamic properties must also implement __isset().

See https://github.com/php/php-src/blob/PHP-7.0.0/UPGRADING#L629 - Thanks to Bell for the hint!