如何通过PHP中的特定键对数组中的数组进行排序[重复]

Possible Duplicate:
Sorting an associative array in PHP
How to sort a multidimensional array by a certain key?

I would like to know how can I sort an array in array by a specific key.

For example:

$array = array( 0 => array("id"=>25), 1 => array("id"=>15) , 2 => array("id"=>19) );

now I want to sort the array by the key "id", i'm expecting this result:

$array = array( 0 => array("id"=>15), 1 => array("id"=>19) , 2 => array("id"=>25) );

Anybody can help ?

Thanks

Hope this may work.

function cmp($a, $b){
    return $a['id'] - $b['id'];
}
usort($array, 'cmp');