Search in Array of Arrays - php

Question

I have arrays like this:
Array
(
[license_id] => 2
[email_address] => alib#email.com
[user_id] => 2
[first_watch] =>
)
Array
(
[license_id] => 1
[email_address] => user1#email.com
[user_id] =>
[first_watch] =>
)
These arrays will be embedded in an array, so the result is an array of arrays.
I need to search within these items for a specific user_id.
so for instance i want to find out if the big array includes an array that has the user_id = 2 and return the key of that array.
Array
(
[0] => Array
(
[license_id] => 2
[email_address] => alib#email.com
[user_id] => 2
[first_watch] =>
)
[1] => Array
(
[license_id] => 1
[email_address] => user1#email.com
[user_id] =>
[first_watch] =>
)
)
What I want from this example would the key, [0] if I'm looking for 2 (user_id). I'll be always looking for a user_id so that's fixed.
I used foreach to loop through items and in_array() to find the item, but the result is not always as I expect, sometimes searching for something that doesn't exist will still return a key.
You guys have any suggestions on achieving this?

Answer 1

PHP >= 5.5.0
Extract the user_id column and search:
$key = array_search(2, array_column($array, 'user_id'));
PHP < 5.5.0
Map and get user_id:
$key = array_search(2, array_map(function($v) { return $v['user_id']; }, $array));
Or loop and check:
foreach($array as $k => $v) {
if($v['user_id'] == 2) {
$key = $k;
break;
}
}

Answer 2

I would do this:
//my_array being your multidimensional array
//my_id being the id you're looking for
$index = null;
for($i=0;$i<count($my_array);$i++)
{
//is the id in this sub array?
if($my_array[$i]['user_id'] == $my_id)
{
//get the index you're searching for
$index = $i;
}
}
//check if an index was found
if($index != null)
{
//display the index you're searching for
echo $index;
}
It's a little bit long but it allows you to do add stuff to the code if you need to.