counting array elements in OOP

[toptomato]

I'm trying to set up some vars in a class and need to count an object in an array but am not doing it right obviously..

proceedurally it woud be this

$productIDs = array(12, 78, 79, 153);
$count = count($productIDs); 

but that causes an error in this context.

class myClass extends base {
    $productIDs = array(12, 78, 79, 153);
    $count = count($productIDs);
} 

i've this and a few other variations below...

$count = count($this->productIDs); 

big thanks for any help on this...

[NogDog]

If you really need to know the size of the array without wanting to simply access the array directly and do a count() as needed, you could just create a method, so it's always up-to-date any regardless of any changes made to the array:

class myClass extends base {
    private $productIDs = array(12, 78, 79, 153); // change to public if you really want direct read/write access

    /**
     * Use this when you just want the count without actually accessing the array
     */
    public function getCount()
    {
        return count($this->prodcutIDs);
    }
} 

[toptomato]

thanks NogDog. for some reasons i'm getting errors..?

class hazMatProduct extends base {

private $hazMatProdsOne = array(115,162);
private $hazMatProdsTwo = array(49, 83, 82);
 
public function getCount($arr) {
        return count($this->$arr);
    }
$countHM1 = getCount($hazMatProdsOne);

var $cartAmount = 300; 

if i comment out the function getCount and $countHM1 the errors go away.
maybe has to do w/ framework i'm using

[Derokorian]

The "function" is actually a method that's a member of a class yet you are trying to call it like a regular function. Instead you need to instantiate the class and then call the method from that object.

class hazMatProduct extends base {

private $hazMatProdsOne = array(115,162);
private $hazMatProdsTwo = array(49, 83, 82);
 
public function getCount($arr) {
      if( $arr ==  1 || $arr == "one" )
         return count($this->hazMatProdsOne);
      if( $arr == 2 || $arr == "two" )
         return count($this->hazMatProdsTwo);
    }
}
$hmp = new hazMatProduct();
$countHM1 = $hmp->getCount("One"); 

[toptomato]

thanks for answering my post.

but i need that variable, the array length, for another function that needs to be defined within the class. can you advise?

i like yer getCount function, thanks

[gvre]

Why don't you use NogDog's answer?

[NogDog]

thanks for answering my post.

but i need that variable, the array length, for another function that needs to be defined within the class. can you advise?

i like yer getCount function, thanks

You can either call that method internally whenever you need it, or just do a $count=count($this->hazMatProdsOne) itself within the method where it's needed. If you really feel it's desirable to have the count as a separate variable (for now I've not seen any reason to, as far as my programming tastes go), you could populate it via your constructor method:

class Foo
{
    private $hazMatProdsOne = array(115,162);
    private $hazMatProdsTwo = array(49, 83, 82); 
    private $countHazMatProdsOne;
    private $countHazMatProdsTwo;
    public function __construct()
    {
        $this->countHazMatProdsOne = count($this->$hazMatProdsOne);
        $this->countHazMatProdsTwo = count($this->$hazMatProdsTwo);
    }
} 

Of course, if we're really going to get all OOP about this, it might be that each of those "hasMatProds" arrays should actually be objects, whose class might contain a count() method.