我最近尝试了一个登录系统，在连接到数据库后，一切仍然无法正常工作，其中的所有值$_SESSION['somevalue']都给出了类似这样的错误：
Notice: Undefined index: submit in C:\wamp\www\demo.php on line 82
每次$_SESSION使用时都是如此，表格tz_members已创建并且工作正常。任何帮助将不胜感激。这是我的代码
<?php
define('INCLUDE_CHECK',true);
require 'connect.php';
require 'functions.php';
// Those two files can be included only if INCLUDE_CHECK is defined
session_start();
session_name('tzLogin');
// Starting the session
session_set_cookie_params(2*7*24*60*60);
// Making the cookie live for 2 weeks
session_start();
if($_SESSION['id'] && !isset($_COOKIE['tzRemember']) && !$_SESSION['rememberMe'])
{
// If you are logged in, but you don't have the tzRemember cookie (browser restart)
// and you have not checked the rememberMe checkbox:
$_SESSION = array();
session_destroy();
// Destroy the session
}
if(isset($_GET['logoff']))
{
$_SESSION = array();
session_destroy();
header("Location: demo.php");
exit;
}
if($_POST['submit']=='Login')
{
// Checking whether the Login form has been submitted
$err = array();
// Will hold our errors
if(!$_POST['username'] || !$_POST['password'])
$err[] = 'All the fields must be filled in!';
if(!count($err))
{
$_POST['username'] = mysql_real_escape_string($_POST['username']);
$_POST['password'] = mysql_real_escape_string($_POST['password']);
$_POST['rememberMe'] = (int)$_POST['rememberMe'];
// Escaping all input data
$row = mysql_fetch_assoc(mysql_query("SELECT id,usr FROM tz_members WHERE usr='{$_POST['username']}' AND pass='".md5($_POST['password'])."'"));
if($row['usr'])
{
// If everything is OK login
$_SESSION['usr']=$row['usr'];
$_SESSION['id'] = $row['id'];
$_SESSION['rememberMe'] = $_POST['rememberMe'];
// Store some data in the session
setcookie('tzRemember',$_POST['rememberMe']);
}
else $err[]='Wrong username and/or password!';
}
if($err)
$_SESSION['msg']['login-err'] = implode('<br />',$err);
// Save the error messages in the session
header("Location: demo.php");
exit;
}
else if($_POST['submit']=='Register')
{
// If the Register form has been submitted
$err = array();
if(strlen($_POST['username'])<4 || strlen($_POST['username'])>32)
{
$err[]='Your username must be between 3 and 32 characters!';
}
if(preg_match('/[^a-z0-9\-\_\.]+/i',$_POST['username']))
{
$err[]='Your username contains invalid characters!';
}
if(!checkEmail($_POST['email']))
{
$err[]='Your email is not valid!';
}
if(!count($err))
{
// If there are no errors
$pass = substr(md5($_SERVER['REMOTE_ADDR'].microtime().rand(1,100000)),0,6);
// Generate a random password
$_POST['email'] = mysql_real_escape_string($_POST['email']);
$_POST['username'] = mysql_real_escape_string($_POST['username']);
// Escape the input data
mysql_query(" INSERT INTO tz_members(usr,pass,email,regIP,dt)
VALUES(
'".$_POST['username']."',
'".md5($pass)."',
'".$_POST['email']."',
'".$_SERVER['REMOTE_ADDR']."',
NOW()
)");
if(mysql_affected_rows($link)==1)
{
send_mail( 'demo-test@tutorialzine.com',
$_POST['email'],
'Registration System Demo - Your New Password',
'Your password is: '.$pass);
$_SESSION['msg']['reg-success']='We sent you an email with your new password!';
}
else $err[]='This username is already taken!';
}
if(count($err))
{
$_SESSION['msg']['reg-err'] = implode('<br />',$err);
}
header("Location: demo.php");
exit;
}
$script = '';
if($_SESSION['msg'])
{
// The script below shows the sliding panel on page load
$script = '
<script type="text/javascript">
$(function(){
$("div#panel").show();
$("#toggle a").toggle();
});
</script>';
}
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>A Cool Login System With PHP MySQL & jQuery | Tutorialzine demo</title>
<link rel="stylesheet" type="text/css" href="demo.css" media="screen" />
<link rel="stylesheet" type="text/css" href="login_panel/css/slide.css" media="screen" />
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js"></script>
<!-- PNG FIX for IE6 -->
<!-- http://24ways.org/2007/supersleight-transparent-png-in-ie6 -->
<!--[if lte IE 6]>
<script type="text/javascript" src="login_panel/js/pngfix/supersleight-min.js"></script>
<![endif]-->
<script src="login_panel/js/slide.js" type="text/javascript"></script>
<?php echo $script; ?>
</head>
<body>
<!-- Panel -->
<div id="toppanel">
<div id="panel">
<div class="content clearfix">
<div class="left">
<h1>The Sliding jQuery Panel</h1>
<h2>A register/login solution</h2>
<p class="grey">You are free to use this login and registration system in you sites!</p>
<h2>A Big Thanks</h2>
<p class="grey">This tutorial was built on top of <a href="http://web-kreation.com/index.php/tutorials/nice-clean-sliding-login-panel-built-with-jquery" title="Go to site">Web-Kreation</a>'s amazing sliding panel.</p>
</div>
<?php
if(!$_SESSION['id']):
?>
<div class="left">
<!-- Login Form -->
<form class="clearfix" action="" method="post">
<h1>Member Login</h1>
<?php
if($_SESSION['msg']['login-err'])
{
echo '<div class="err">'.$_SESSION['msg']['login-err'].'</div>';
unset($_SESSION['msg']['login-err']);
}
?>
<label class="grey" for="username">Username:</label>
<input class="field" type="text" name="username" id="username" value="" size="23" />
<label class="grey" for="password">Password:</label>
<input class="field" type="password" name="password" id="password" size="23" />
<label><input name="rememberMe" id="rememberMe" type="checkbox" checked="checked" value="1" /> Remember me</label>
<div class="clear"></div>
<input type="submit" name="submit" value="Login" class="bt_login" />
</form>
</div>
<div class="left right">
<!-- Register Form -->
<form action="" method="post">
<h1>Not a member yet? Sign Up!</h1>
<?php
if($_SESSION['msg']['reg-err'])
{
echo '<div class="err">'.$_SESSION['msg']['reg-err'].'</div>';
unset($_SESSION['msg']['reg-err']);
}
if($_SESSION['msg']['reg-success'])
{
echo '<div class="success">'.$_SESSION['msg']['reg-success'].'</div>';
unset($_SESSION['msg']['reg-success']);
}
?>
<label class="grey" for="username">Username:</label>
<input class="field" type="text" name="username" id="username" value="" size="23" />
<label class="grey" for="email">Email:</label>
<input class="field" type="text" name="email" id="email" size="23" />
<label>A password will be e-mailed to you.</label>
<input type="submit" name="submit" value="Register" class="bt_register" />
</form>
</div>
<?php
else:
?>
<div class="left">
<h1>Members panel</h1>
<p>You can put member-only data here</p>
<a href="registered.php">View a special member page</a>
<p>- or -</p>
<a href="?logoff">Log off</a>
</div>
<div class="left right">
</div>
<?php
endif;
?>
</div>
</div> <!-- /login -->
<!-- The tab on top -->
<div class="tab">
<ul class="login">
<li class="left"> </li>
<li>Hello <?php echo $_SESSION['usr'] ? $_SESSION['usr'] : 'Guest';?>!</li>
<li class="sep">|</li>
<li id="toggle">
<a id="open" class="open" href="#"><?php echo $_SESSION['id']?'Open Panel':'Log In | Register';?></a>
<a id="close" style="display: none;" class="close" href="#">Close Panel</a>
</li>
<li class="right"> </li>
</ul>
</div> <!-- / top -->
</div> <!--panel -->
<div class="pageContent">
<div id="main">
<div class="container">
<h1>A Cool Login System</h1>
<h2>Easy registration management with PHP & jQuery</h2>
</div>
<div class="container">
<p>This is a simple example site demonstrating the <a href="http://tutorialzine.com/2009/10/cool-login-system-php-jquery/">Cool Login System tutorial</a> on <strong>Tutorialzine</strong>. You can start by clicking the <strong>Log In | Register</strong> button above. After registration, an email will be sent to you with your new password.</p>
<p><a href="registered.php" target="_blank">View a test page</a>, only accessible by <strong>registered users</strong>.</p>
<p>The sliding jQuery panel, used in this example, was developed by <a href="http://web-kreation.com/index.php/tutorials/nice-clean-sliding-login-panel-built-with-jquery" title="Go to site">Web-Kreation</a>.</p>
<p>You are free to build upon this code and use it in your own sites.</p>
<div class="clear"></div>
</div>
<div class="container tutorial-info">
This is a tutorial zine demo.
查看
<a href="http://tutorialzine.com/2009/10/cool-login-system-php-jquery/" target="_blank">original tutorial</a>, or download the
<a href="demo.zip">source files</a>. </div>
</div>
</div>
</body>
</html>
我知道这里不需要整个代码，它让我的问题看起来很混乱，但我想以防万一有人需要它。