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PHP Build a Simple PHP Application Integrating with PayPal Array Keys

The array below contains a list of books. Each element in the array has the book’s title as its value and the ISBN as it

I've been on this one for a couple days now. Really confused! If someone wouldn't mind helping me that would be awesome!

1 Answer


They are asking you to modify the foreach() loop to include the array keys and then take that array key and put it into a variable called $isbn. Remember, you can use a foreach loop one of two ways: foreach($array as $value) and foreach($array as $key => $value). Once you allow to loop to use the array key, just assign it to the variable $isbn or if you named the array key in the loop $isbn, just add another $ to the front of it like so: $$isbn. Hope I helped you enough for you to get it without giving you the direct answer.