[ALUG] PHP help wanted - arrays and foreach

9 Feb 2010

      I'm trying to understand/debug a bit of PHP, the code is as follows:-

    if (isset($data['date']))
    {
        if (is_array($data['date']))
        {
            foreach($data['date'] as $key => $date)
            {
                $date = $this->_convertDate(trim($date));
                if (!$date) unset($data['date'][$key]);
                else $data['date'][$key] = $date;
                dbglog($data, "Converted data");
            }
        }
        else
        {
            unset($data['date']);
        }
    }

What's happening is that it always ends up with nothing in $data
(what's reported by that dbglog()).

I'm confused by what happens with that foreach as, as far as I can
see, $data['date'] is just what I would call a list in python, it's
not an array indexed by values it's just a sequential array.

So, in the foreach loop $key gets the values from the $date array and
$date is empty (confirmed by further dbglog()).

Am I understanding this right?  If I create an array:-

    $aa = array('abc', 'def', 'ghi', 'jkl');

Then do:-

    foreach $aa as $x => $y
    {
        // what do I get for $x and $y here?
    }

Sorry this is a bit confused/muddled, I'm definitely not a PHP programmer.

-- 
Chris Green