PHP vs JS

gistfile1.php

<?php
/* PHP */                                     /* JavaScript */
mb_strpos($myEmail, '@');                     myEmail.indexOf('@');
str_replace('@', '[at]', $myEmail);           myEmail.replace('@', '[at]');
mb_substr($myEmail, 0, 5);                    myEmail.substr(0, 5);
mb_strlen($myEmail);                          myEmail.length;
(int) '10';                                   parseInt('10');
array_key_exists('name', $user);              'name' in user;
in_array('Book 1', $userBooks);               userBooks.includes('Book 1');
time();                                       Date.now();
var_dump($varToDebug);                        console.log(varToDebug);
json_encode($user);                           JSON.strinfigy(user);
json_decode('{}');                            try { JSON.parse('{}'); } catch (error) {}