Question

I have tried the array_reduce and array_merge methods but they don’t seem to do what I expected. Is there a way of doing this without a foreach?

I need to convert an array such as:

Array
(
    [0] => Array
        (
            [id] => 2
        )

    [1] => Array
        (
            [id] => 3
        )

    [2] => Array
        (
            [id] => 4
        )

)

Into:

Array
(
    [0] => 2
    [1] => 3
    [2] => 4
)

Answer 1

You could use array_map

$flat = array_map(function($el) {  return $el['id']; }, $arr);

Not this is for php 5.3. If you are using 5.2 youll have to define a function or use create_function instead of passing in an anonymous like i have here.