find element in arrat php

1array_search ( mixed $needle , array $haystack , bool $strict = false ) : int|string|false
2
3<?php
4$array = array(0 => 'blue', 1 => 'red', 2 => 'green', 3 => 'red');
5
6$key = array_search('green', $array); // $key = 2;
7$key = array_search('red', $array);   // $key = 1;
8?>

1$userdb=Array
2(
3    (0) => Array
4        (
5            (uid) => '100',
6            (name) => 'Sandra Shush',
7            (url) => 'urlof100'
8        ),
9
10    (1) => Array
11        (
12            (uid) => '5465',
13            (name) => 'Stefanie Mcmohn',
14            (pic_square) => 'urlof100'
15        ),
16
17    (2) => Array
18        (
19            (uid) => '40489',
20            (name) => 'Michael',
21            (pic_square) => 'urlof40489'
22        )
23);
24
25simply u can use this
26
27$key = array_search(40489, array_column($userdb, 'uid'));

1$array = [
2    'clothes' => 't-shirt',
3    'size'    => 'medium',
4    'color'   => 'blue',
5];
6 
7extract($array);
8 
9echo("$clothes $size $color"); // t-shirt medium blue
10