how get the search data from the array in php code example

Example 1: array_search in php

<?php
$array = array(0 => 'blue', 1 => 'red', 2 => 'green', 3 => 'red');

$key = array_search('green', $array); // $key = 2;
$key = array_search('red', $array);   // $key = 1;
?>

Example 2: search php array

$userdb = array(
    array(
        'uid' => '100',
        'name' => 'Sandra Shush',
        'pic_square' => 'urlof100'
    ),
    array(
        'uid' => '5465',
        'name' => 'Stefanie Mcmohn',
        'pic_square' => 'urlof100'
    ),
    array(
        'uid' => '40489',
        'name' => 'Michael',
        'pic_square' => 'urlof40489'
    )
);