in_array begin with example php

Example 1: in_array

<?php
/**
in_array ( mixed $needle , array $haystack [, bool $strict = FALSE ] ) : bool
*/

$os = array("Mac", "NT", "Irix", "Linux");
if (in_array("Irix", $os)) {
    echo "Got Irix";
}
if (in_array("mac", $os)) {
    echo "Got mac";
}
?>

Example 2: in_array php

<?php
$os = array("Mac", "NT", "Irix", "Linux");
if (in_array("Irix", $os)) {
    echo "Existe Irix";
}
if (in_array("mac", $os)) {
    echo "Existe mac";
}
?>

Example 3: check null in_array php

if (!empty($data_days) && in_array(1, $data_days, true)){ // use numeric value 1, not string