Sorting two-dimensional array by date

Question

Is there a way I can sort the following array into the correct chronological order ?

[0] => Array
    (
        [date] => Sat, 12 Feb 2011 16:55:13 -0500
        [title] => Product 1
        [link] => http://blabla/product-1
    )

[1] => Array
    (
        [date] => Sat, 25 Sep 2010 17:52:24 -0400
        [title] => Product 2
        [link] => http://blabla/product-2
    )

[2] => Array
    (
        [date] => Sun, 05 Dec 2010 17:41:32 -0500
        [title] => Product 3
        [link] => http://blabla/product-3
    )

[3] => Array
    (
        [date] => Sun, 28 Nov 2010 09:14:39 -0500
        [title] => Product 4
        [link] => http://blabla/product-4
    )

[4] => Array
    (
        [date] => Tue, 07 Dec 2010 18:43:45 -0500
        [title] => Product 5
        [link] => http://blabla/product-5
    )

The array, from a rss feed, comes to me like this.

I would like to sort the array in chronological order (based on [date] obviously) : Product 1, Product 5, Product 3, Product 4, Product 2

In order to be able to do display the latest products in the real order (not in the strange order they gave me ! - btw, fake products names, the order is really totally random )

Thanks a lot !

Answer 1

Use usort: http://www.phpbuilder.com/manual/function.usort.php

You write a comparison function that compares two "elements" (in this case, your date strings), and returns the correct order for them.

Edit: you could use strtotime: http://php.net/manual/en/function.strtotime.php to convert the date string to a timestamp, and then return the comparison of the resulting timestamps.

Answer 2

You can use array_multisort to order the original array according to the order of a sorted array of date values:

$keyValues = array();
foreach ($arr as $item) {
    $keyValues[] = strtotime($item['date']);
}
sort($keyValues);
array_multisort($arr, $keyValues);

Answer 3

Use usort function . http://php.net/manual/en/function.usort.php