efficient way to search object in an array by a property

Question

well, having something like:

$array[0]->id = \'one\';
$array[0]->color = \'white\';
$array[1]->id = \'two\';
$array[1]->color = \'red\';
$array[2         


        

Answer 1

Something I like to do in these situations is to create a referential array, thus avoiding having to re-copy the object but having the power to use the reference to it like the object itself.

$array['one']->id = 'one';
$array['one']->color = 'white';
$array['two']->id = 'two';
$array['two']->color = 'red';
$array['three']->id = 'three';
$array['three']->color = 'blue';

Then we can create a simple referential array:

$ref = array();
foreach ( $array as $row )
    $ref[$row->id] = &$array[$row->id];

Now we can simply test if an instance exists in the array and even use it like the original object if we wanted:

if ( isset( $ref['one'] ) )
    echo $ref['one']->color;

would output:

white

If the id in question did not exist, the isset() would return false, so there's no need to iterate the original object over and over looking for a value...we just use PHP's isset() function and avoid using a separate function altogether.

Please note when using references that you want use the "&" with the original array and not the iterator, so using &$row would not give you what you want.