PHP - How to merge arrays inside array

Lekhnath picture Lekhnath · Jun 11, 2013 · Viewed 47.6k times · Source

How to merge n number of array in php. I mean how can I do the job like :
array_merge(from : $result[0], to : $result[count($result)-1])
OR
array_merge_recursive(from: $result[0], to : $result[count($result) -1])


Where $result is an array with multiple arrays inside it like this :

$result = Array(
0 => array(),//associative array
1 => array(),//associative array
2 => array(),//associative array
3 => array()//associative array
)

My Result is :

$result = Array(
    0 => Array(
        "name" => "Name",
        "events" => 1,
        "types" => 2
    ),
    1 => Array(
        "name" => "Name",
        "events" => 1,
        "types" => 3
    ),
    2 => Array(
        "name" => "Name",
        "events" => 1,
        "types" => 4
    ),
    3 => Array(
        "name" => "Name",
        "events" => 2,
        "types" => 2
    ),
    4 => Array(
        "name" => "Name",
        "events" => 3,
        "types" => 2
    )
)

And what I need is

$result = Array(
"name" => "name",
"events" => array(1,2,3),
"types" => array(2,3,4)
)

Answer

complex857 picture complex857 · Jun 11, 2013

array_merge can take variable number of arguments, so with a little call_user_func_array trickery you can pass your $result array to it:

$merged = call_user_func_array('array_merge', $result);

This basically run like if you would have typed:

$merged = array_merge($result[0], $result[1], .... $result[n]);

Update:

Now with 5.6, we have the ... operator to unpack arrays to arguments, so you can:

$merged = array_merge(...$result);

And have the same results. *

* The same results as long you have integer keys in the unpacked array, otherwise you'll get an E_RECOVERABLE_ERROR : type 4096 -- Cannot unpack array with string keys error.