iterating through multi dimensional arrays

Question

I am trying to get the item id, and then all option_name/option_values within that item id. So I end up with, ID: 123, Color: Blue, Size: 6. ID: 456, Color: Yellow, Size: 8.

Answer 1

This is because your array contains the POSSIBILITY of those keys existing, not guaranteed. There's a few different approaches you could take, such as checking if the key is numeric (seems only numeric keys have the correct array of keys set). But since i dont know your dataset, probably the best universal method is to change your code to check if the key's are set, before trying to use them. So..

foreach($itemlist as $item) {

 foreach($item as $key => $value) {

      if(is_array($value) && array_key_exists('option_name', $value) {

           //--- Your option array is available in here via $value['option_x']

      }

 }

}

Answer 2

Basically, you're looping over the $item array, which looks like this:

array(7) {
   ["ID"]=>string(6) "123"
   ["QTY"]=>string(1) "1"
   ["MODEL"]=>string(11) "sdfsd"
   ["IMAGE"]=>string(0) ""
   [1]=>
       array(3) {
           ["option_name"]=>string(8) "Color"
           ["option_value"]=>string(10) "Blue"
           ["option_price"]=>string(6) "0.0000"
      }

So on the first iteration, $option will be 123, trying to access '123'['option_name'] will issue a warning. What you actually wanted to do is this:

foreach($item[1] as $key => $option)
{
    if ($key !== 'option_price')
    {
        echo $option;
    }
}
//or:
echo $item['ID'], $item[1]['option_name'], $item['option_value'];

That's why your code doesn't produce the desired result.
If the sub-array doesn't always have 1 as a key, try:

foreach($item as $foo)
{
    if (is_array($foo))
    {
        echo $foo['option_name'], $foo['option_value'];
        break;//we have what we needed, no need to continue looping.
    }
}

Here's the most generic approach to get all options (irrespective of how many)

foreach($itemlist as $item)
{
    echo $item['ID'];
    foreach($item as $sub)
    {
        if (is_array($sub))
        {
            foreach($sub as $key => $option)
            {
                echo $key, ' => ', $option;
            }
        }
    }
}

But seeing as your options arrays look like they all have numeric indexes, you could just as well try this:

foreach($itemlist as $item)
{
    echo $item['ID'];
    for ($i=1;isset($item[$i]);$i++)
    {
        foreach($item[$i] as $key => $option)
        {
            echo $key, ' => ', $option;
        }
    }
}

You could replace the for loop with:

$i=0;//or $i = 1
while(isset($item[++$i]))// or isset($item[$i++]), if $i is 1

Answer 3

You could try something like:

array_walk_recursive($itemlist, function($value, $key) {
    if (in_array($key, array("ID", "option_name", "option_value")))
        echo "$key: $value\n";
});