how to check inside of string in php code example

Example 1: how to check if a string contains a substring in php

$a = 'How are you?';

if (strpos($a, 'are') !== false) {
    echo 'true';
}

Example 2: php string contains

$mystring = 'abc';
$findme   = 'a';
$pos = strpos($mystring, $findme);