How to array_merge_recursive() an array?

Question

I am just starting to understand how array_merge_recursive()works.

Can someone tell me how to use this php function with an array?

I am trying to do the following:

$ars[] = array("name_a" => array("color" => array("red")));
$ars[] = array("name_a" => array("color" => array("green", "blue")));
$ars[] = array("name_b" => array("color" => array("green", "tangerine")));
$ars[] = array("name_c" => array("color" => array("purple", "blue","red")));
$ars[] = array("name_c" => array("color" => array("green", "blue","green","beige")));
$ars[] = array("name_b" => array("color" => array("green", "blue","yellow")));

$result = array_merge_recursive($ars);

for some reason that I don't know, that does not work. The only way it is working for me is as follows:

$ars1 = array("name_a" => array("post_id" => array("red")));
$ars2 = array("name_a" => array("post_id" => array("green", "blue")));
$ars3 = array("name_b" => array("post_id" => array("green", "blue")));
$ars4 = array("name_c" => array("post_id" => array("green", "blue","red")));
$ars5 = array("name_c" => array("post_id" => array("green", "blue","green","beige")));
$ars6 = array("name_b" => array("post_id" => array("green", "blue","yellow")));
$result = array_merge_recursive($ars1,$ars2,$ars3,$ars4,$ars5,$ars6);

So, how can I put an array inside the array_merge_recursive(); function?

Quoting from the docs: array_merge_recursive — Merge __two or more arrays__ recursively (my emphasis).... you're trying to merge a single array..... explain what you're trying to achieve — Mark Baker
– Mark Baker, Commented Nov 27, 2014 at 23:19
At a guess: $result = call_user_func_array('array_merge_recursive', $ars); See demo — Mark Baker
– Mark Baker, Commented Nov 27, 2014 at 23:21

0xbb · Accepted Answer · 2014-11-27 23:32:51Z

2

If you want to call array_merge_recursive(); or any other function with an array mapped as args you can use:

$result = call_user_func_array('array_merge_recursive', $ars);

Starting with PHP 5.6 there is a special operator for that:

$result = array_merge_recursive(...$ars);

answered Nov 27, 2014 at 23:32

0xbb

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Nexx Tea · Accepted Answer · 2014-11-27 23:21:01Z

0

I think you answered your own question didn't you?

array_merge_recursive() requires two parameters of array type so that you can "merge" them. what exactly are you merging with one array?

answered Nov 27, 2014 at 23:21

Nexx Tea

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