Is there a function to extract a 'column' from an array in PHP?

Question

I have an array of arrays, with the following structure :

array(array(\'page\' => \'page1\', \'name\' => \'pagename1\')
      array(\'page\' => \'pa         


        

Answer 1

You can extend the ArrayIterator class and override the method mixed current(void).

class Foo extends ArrayIterator {
  protected $index;
  public function __construct($array, $index) {
    parent::__construct($array);
    $this->index = $index;
  }

  public function current() {
    $c = parent::current();
    return isset($c[$this->index]) ? $c[$this->index] : null;
  }
}

$a = array(
  array('page' => 'page1', 'name' => 'pagename1'),
  array('name' => '---'),
  array('page' => 'page2', 'name' => 'pagename2'),
  array('page' => 'page3', 'name' => 'pagename3')
);

$f = new Foo($a, 'page');
foreach($f as $e) {
  echo $e, "\n";
}

prints

page1

page2
page3