[PHP] How to sort arrays inside an array?

Question

Hello there,

I need to sort arrays inside an array of array based on one of the array's array value.

For example:

$data = array( array( 1, "Article One", 132, 12402773, 3 ),
               array( 2, "Article Two", 251, 12519283, 5 ),
               array( 3, "Article Three", 107, 12411321, 3 ),
               array( 4, "Article Four", 501, 12228135, 4 ) );

By default, if I print the 2nd element of each array:

• Article One
• Article Two
• Article Three
• Article Four

I need to sort it in a descending order by the 3rd element of the child-array.

So it would be like this:

• Article Four
• Article Two
• Article One
• Article Three

Because 501 > 251 > 132 > 107.

Any suggestion?

Answer 1

array_multisort :)

Answer 2

I typically use a usort() for this:

function compare($a, $b) {
    return ($a[2] > $b[2]);
}

usort($data, 'compare');

Answer 3

You will need to use recursion.

Check these links out:

• Link One
• Link Two
• Link Three
• Link Four

Check this out first - Link Five