PHP Function Arguments: Array of Objects of a Specific Class

No, it's not possible to do directly. You might try this "clever" trick instead:

public function addPages(array $pages)
{
    foreach($pages as $page) addPage($page);
}

public function addPage(My_Page $page)
{
    //
}

But I 'm not sure if it's worth all the trouble. It would be a good approach if addPage is useful on its own.

You can use the instanceof operator, to check if an object is an instance of :

• A class
• Or a child class of that class
• Or an instance of a class that implements an interface

Which means that it cannot be used to detect if your object is an instance of a specific class -- as it will say "yes" if your object is an instance of a child-class of that class.

For instance, this portion of code :

class ClassA {}
class ClassB extends ClassA {}

$a = new ClassB();
if ($a instanceof ClassA) {
    echo '$a is an instanceof ClassA<br />';
}
if ($a instanceof ClassB) {
    echo '$a is an instanceof ClassB<br />';
}

Will get you this output :

$a is an instanceof ClassA
$a is an instanceof ClassB

$a, in a way, is an instance of ClassA, as ClassB is a child-class of ClassA.

And, of course, $a is also an instance of ClassB -- see the line where it's instanciated.

A solution to get all instances of a class is to keep records of instantiated classes when you create them:

class Foo
{
  static $instances=array();
  public function __construct() {
    Foo::$instances[] = $this;
  }
}

Now the globally accessible array Foo::$instances will contain all instances of that class. Your question was a bit broad so I can not exactly say if this is what you're looking for. If not, it hopefully helps to make it more clear what you're looking for.