sorting - How to perform a natural sort in php using usort

Question

Does anyone know what the function is to perform a natural order sort using the usort function in PHP on an object.

Lets say the object ($obj->Rate)has a range of values in

$obj->10
$obj->1
$obj->2
$obj->20
$obj->22

What is I am trying to get the sort function to return

$obj->22
$obj->20
$obj->10
$obj->2
$obj->1

As my current standard sort function

function MySort($a, $b)
{ 
    if ($a->Rate == $b->Rate)
    {
        return 0;
    } 
    return ($a->Rate < $b->Rate) ? -1 : 1;
}

is returning

$obj->1
$obj->10
$obj->2
$obj->20
$obj->22

Answer 1

Use strnatcmp for your comparison function. e.g. it's as simple as

function mysort($a, $b) {
   return strnatcmp($a->rate, $b->rate);
}