Hi, I was needing some help with preventing repeat sign ups. I need a query to check the submitted email address ($e) is currently in the database by attempting to select that record. If it's not in the database, then it's safe to register.
Here is the existing code (with/out) the prevention of repeated sign ups. Please tell me on which lines (where to add) the code you provide in your replies. If at all possible please provide the code I should add also. I'm noobie at php with less than two weeks experience with it.
<?php # Script 7.3 - register.php
$page_title = 'Register';
include ('./header.html');
// Check if the form has been submitted.
if (isset($_POST['submitted'])) {
$errors = array(); // Initialize error array.
// Check for a first name.
if (empty($_POST['first_name'])) {
$errors[] = 'You forgot to enter your first name.';
} else {
$fn = trim($_POST['first_name']);
}
// Check for a last name.
if (empty($_POST['last_name'])) {
$errors[] = 'You forgot to enter your last name.';
} else {
$ln = trim($_POST['last_name']);
}
// Check for an email address.
if (empty($_POST['email'])) {
$errors[] = 'You forgot to enter your email address.';
} else {
$e = trim($_POST['email']);
}
// Check for a password and match against the confirm password.
if (!empty($_POST['password1'])) {
if ($_POST['password1'] != $_POST['password2']) {
$errors[] = 'Your password did not match the confirmed password.';
} else {
$p = trim($_POST['password1']);
}
} else {
$errors[] = 'You forgot to enter your password.';
}
if (empty($errors)) { // If everythings okay.
// Register the user in the database.
require_once ('mysql_connect.php'); // Connect to the db.
$link = mysql_connect('localhost', 'username', 'password');
if (!$link) {
die('Could not connect: ' . mysql_error());
}
echo 'Connected successfully';
mysql_close($link);
$link = mysql_connect('localhost', 'username', 'password');
if (!$link) {
die('Not connected : ' . mysql_error());
}
// Check for previous registration.
$query = "SELECT user_id FROM users WHERE email='$e'";
$result = mysql_query($query);
if (mysql_num_rows($result) == 0) {
} else {
echo // Already registered.
'<h1 id="mainhead">Error!</h1>
<p class="error">This email address has already been registered.</p>;
}
// make sitename the current db
$db_selected = mysql_select_db('sitename', $link);
if (!$db_selected) {
die ('Can\'t use sitename : ' . mysql_error());
}
// make sitename the current db
$db_selected = mysql_select_db('sitename', $link);
if (!$db_selected) {
die ('Can\'t use sitename : ' . mysql_error());
}
// Make the query.
$query = "INSERT INTO users (first_name, last_name, email, password, registration_date) VALUES ('$fn', '$ln', '$e', SHA
('$p'), NOW() )";
$result = @mysql_query ($query); // Run the query.
if ($result) { // If it ran OK.
// Send an email, if desired.
// Print a message.
echo '<h1 id="mainhead">Thank you!</h1>
<p>You are now registered. In Chapter 9 you will actually be able to log in!</p><p><br/></p>';
// Include the footer and quit the script (to not show the form).
include ('./footer.html');
exit();
} else { // If it did not run OK.
echo '<h1 id="mainhead">System Error</h1>
<p class="error">You could not be registered due to a system error. We apologize for any inconvenience.</p>'; // Public message.
echo '<p>' . mysql_error() . '<br/><br/>Query: ' . $query . '</p>'; // Debugging message.
include ('./footer.html');
exit();
}
mysql_close(); // Close the database connection.
} else { // Report errors.
echo '<h1 id="mainhead">Error!</h1>
<p class="error">The following error(s) occurred:<br/>';
foreach ($errors as $msg) { // Print each error.
echo " - $msg<br/>\n";
}
echo '</p><p>Please try again</p><p><br/></p>';
} // End of if (empty($errors)) IF.
} // End of the main Submit conditional.
?>
<h2>Register</h2>
<form action="register.php" method="post">
<p>First Name: <input type="text" name="first_name" size="15" maxlength="15" value="<?php if (isset($_POST
['first_name'])) echo $_POST['first_name']; ?>" /></p>
<p>Last Name: <input type="text" name="last_name" size="15" maxlength="30" value="<?php if (isset($_POST['last_name']))
echo $_POST['last_name']; ?>" /></p>
<p>Email Address: <input type="text" name="email" size="20" maxlength="40" value"<?php if (isset($_POST['email'])) echo
$_POST['email']; ?>" /></p>
<p>Password: <input type="password" name="password1" size="10" maxlength="20" /></p>
<p>Confirm Password: <input type="password" name="password2" size="10" maxlength="20" /></p>
<p><input type="submit" name="submit" value="Register" /></p>
<input type="hidden" name="submitted" value="TRUE" />
</form>
<?php
include ('./footer.html');
?>
