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

The thing with performance of data structures is not only how to get but mostly how to store my data.

If you are free to design your array, use an associative array:

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

Finding is then the most cheap: $one = $array['one];

UPDATE:

If you cannot modify your array constitution, you could create a separate array which maps ids to indexes. Finding an object this way does not cost any time:

$map['one'] = 0;
$map['two'] = 1;
$map['three'] = 2;
...

getObjectById() then first lookups the index of the id within the original array and secondly returns the right object:

$index = $map[$id];
return $array[$index];