Learning PHP, MySQL, and JavaScript

rnsignup.php (YUI version)

If you prefer to use YUI, here’s an alternative version of rnsignup.php (see Example 20-6). I have highlighted the main differences in bold type and, as you can see, it’s substantially shorter. Please refer to Chapter 19 for details on how the YUI Ajax implementation works.

Example 20-6. rnsignup.php (YUI version)

<?php // rnsignup.php (YUI version)
include_once 'rnheader.php';

echo <<<_END
<script src="yahoo-min.js"></script>
<script src="event-min.js"></script>
<script src="connection-min.js"></script>
<script>
function checkUser(user)
{
    if (user.value == '')
    {
        document.getElementById('info').innerHTML = ''
        return
    }

    params = "user=" + user.value
    callback = { success:successHandler, failure:failureHandler }
    request = YAHOO.util.Connect.asyncRequest('POST',
        'rncheckuser.php', callback, params);
}

function successHandler(o)
{
    document.getElementById('info').innerHTML = o.responseText;
}

function failureHandler(o)
{
    document.getElementById('info').innerHTML =
        o.status + " " + o.statusText;
} </script> <h3>Sign up Form</h3> _END; $error = $user = $pass = ""; if (isset($_SESSION['user'])) destroySession(); if (isset($_POST['user'])) { $user = sanitizeString($_POST['user']); $pass = sanitizeString($_POST['pass']); if ($user == "" || $pass == "") { $error = "Not all fields were entered<br /><br />"; } else { $query = "SELECT * FROM rnmembers WHERE user='$user'"; if (mysql_num_rows(queryMysql($query))) { $error = "That username already exists<br /><br />"; } else ...