将这段代码从mysql转换为mysqli后，在通过登录页面执行时出现错误，并显示以下错误：致命错误：在第127行的dbc.php中的非对象上调用成员函数real_escape_string（）。不幸的是，我不能帮助自己纠正它。...任何帮助将不胜感激。
dbc.php（如下所示）
<?php
/******************** MAIN SETTINGS - PHP LOGIN SCRIPT V2.1 **********************
Please complete wherever marked xxxxxxxxx
/************* MYSQL DATABASE SETTINGS *****************
1. Specify Database name in $dbname
2. MySQL host (localhost or remotehost)
3. MySQL user name with ALL previleges assigned.
4. MySQL password
Note: If you use cpanel, the name will be like account_database
*************************************************************/
define ("DB_HOST", "89.46.111.48"); // set database host
define ("DB_USER", "Sql1120771"); // set database user
define ("DB_PASS","l226266154"); // set database password
define ("DB_NAME","Sql1120771_3"); // set database name
$link = new mysqli(DB_HOST, DB_USER, DB_PASS) or die("Couldn't make connection.");
$db = $link->select_db(DB_NAME) or die("Couldn't select database");
/* Registration Type (Automatic or Manual)
1 -> Automatic Registration (Users will receive activation code and they will be automatically approved after clicking activation link)
0 -> Manual Approval (Users will not receive activation code and you will need to approve every user manually)
*/
$user_registration = 1; // set 0 or 1
define("COOKIE_TIME_OUT", 10); //specify cookie timeout in days (default is 10 days)
define('SALT_LENGTH', 9); // salt for password
//define ("ADMIN_NAME", "admin"); // sp
/* Specify user levels */
define ("ADMIN_LEVEL", 5);
define ("USER_LEVEL", 1);
define ("GUEST_LEVEL", 0);
/*************** reCAPTCHA KEYS****************/
$publickey = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
$privatekey = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
/**** PAGE PROTECT CODE ********************************
This code protects pages to only logged in users. If users have not logged in then it will redirect to login page.
If you want to add a new page and want to login protect, COPY this from this to END marker.
Remember this code must be placed on very top of any html or php page.
********************************************************/
function page_protect() {
session_start();
global $db;
/* Secure against Session Hijacking by checking user agent */
if (isset($_SESSION['HTTP_USER_AGENT']))
{
if ($_SESSION['HTTP_USER_AGENT'] != md5($_SERVER['HTTP_USER_AGENT']))
{
logout();
exit;
}
}
// before we allow sessions, we need to check authentication key - ckey and ctime stored in database
/* If session not set, check for cookies set by Remember me */
if (!isset($_SESSION['user_id']) && !isset($_SESSION['user_name']) )
{
if(isset($_COOKIE['user_id']) && isset($_COOKIE['user_key'])){
/* we double check cookie expiry time against stored in database */
$cookie_user_id = filter($_COOKIE['user_id']);
$rs_ctime = $link->query("select `ckey`,`ctime` from `users` where `id` ='$cookie_user_id'") or die($link->error);
list($ckey,$ctime) = $rs_ctime->fetch_row();
// coookie expiry
if( (time() - $ctime) > 60*60*24*COOKIE_TIME_OUT) {
logout();
}
/* Security check with untrusted cookies - dont trust value stored in cookie.
/* We also do authentication check of the `ckey` stored in cookie matches that stored in database during login*/
if( !empty($ckey) && is_numeric($_COOKIE['user_id']) && isUserID($_COOKIE['user_name']) && $_COOKIE['user_key'] == sha1($ckey) ) {
session_regenerate_id(); //against session fixation attacks.
$_SESSION['user_id'] = $_COOKIE['user_id'];
$_SESSION['user_name'] = $_COOKIE['user_name'];
/* query user level from database instead of storing in cookies */
list($user_level) = mysql_query("select user_level from users where id='$_SESSION[user_id]'")->fetch_row();
$_SESSION['user_level'] = $user_level;
$_SESSION['HTTP_USER_AGENT'] = md5($_SERVER['HTTP_USER_AGENT']);
} else {
logout();
}
} else {
header("Location: login.php");
exit();
}
}
}
function filter($data) {
$data = trim(htmlentities(strip_tags($data)));
if (get_magic_quotes_gpc())
$data = stripslashes($data);
$data = $link->real_escape_string($data);
return $data;
}
function EncodeURL($url)
{
$new = strtolower(ereg_replace(' ','_',$url));
return($new);
}
function DecodeURL($url)
{
$new = ucwords(ereg_replace('_',' ',$url));
return($new);
}
function ChopStr($str, $len)
{
if (strlen($str) < $len)
return $str;
$str = substr($str,0,$len);
if ($spc_pos = strrpos($str," "))
$str = substr($str,0,$spc_pos);
return $str . "...";
}
function isEmail($email){
return preg_match('/^\S+@[\w\d.-]{2,}\.[\w]{2,6}$/iU', $email) ? TRUE : FALSE;
}
function isUserID($username)
{
if (preg_match('/^[a-z\d_]{5,20}$/i', $username)) {
return true;
} else {
return false;
}
}
function isURL($url)
{
if (preg_match('/^(http|https|ftp):\/\/([A-Z0-9][A-Z0-9_-]*(?:\.[A-Z0-9][A-Z0-9_-]*)+):?(\d+)?\/?/i', $url)) {
return true;
} else {
return false;
}
}
function checkPwd($x,$y)
{
if(empty($x) || empty($y) ) { return false; }
if (strlen($x) < 4 || strlen($y) < 4) { return false; }
if (strcmp($x,$y) != 0) {
return false;
}
return true;
}
function GenPwd($length = 7)
{
$password = "";
$possible = "0123456789bcdfghjkmnpqrstvwxyz"; //no vowels
$i = 0;
while ($i < $length) {
$char = substr($possible, mt_rand(0, strlen($possible)-1), 1);
if (!strstr($password, $char)) {
$password .= $char;
$i++;
}
}
return $password;
}
function GenKey($length = 7)
{
$password = "";
$possible = "0123456789abcdefghijkmnopqrstuvwxyz";
$i = 0;
while ($i < $length) {
$char = substr($possible, mt_rand(0, strlen($possible)-1), 1);
if (!strstr($password, $char)) {
$password .= $char;
$i++;
}
}
return $password;
}
function logout()
{
global $db;
session_start();
$sess_user_id = strip_tags($link->real_escape_string($_SESSION['user_id']));
$cook_user_id = strip_tags($link->real_escape_string($_COOKIE['user_id']));
if(isset($sess_user_id) || isset($cook_user_id)) {
$link->query("update `users`
set `ckey`= '', `ctime`= ''
where `id`='$sess_user_id' OR `id` = '$cook_user_id'") or die($link->error);
}
/************ Delete the sessions****************/
unset($_SESSION['user_id']);
unset($_SESSION['user_name']);
unset($_SESSION['user_level']);
unset($_SESSION['HTTP_USER_AGENT']);
session_unset();
session_destroy();
/* Delete the cookies*******************/
setcookie("user_id", '', time()-60*60*24*COOKIE_TIME_OUT, "/");
setcookie("user_name", '', time()-60*60*24*COOKIE_TIME_OUT, "/");
setcookie("user_key", '', time()-60*60*24*COOKIE_TIME_OUT, "/");
header("Location: login.php");
}
// Password and salt generation
function PwdHash($pwd, $salt = null)
{
if ($salt === null) {
$salt = substr(md5(uniqid(rand(), true)), 0, SALT_LENGTH);
}
else {
$salt = substr($salt, 0, SALT_LENGTH);
}
return $salt . sha1($pwd . $salt);
}
function checkAdmin() {
if($_SESSION['user_level'] == ADMIN_LEVEL) {
return 1;
} else { return 0 ;
}
}
?>登录页面
<?php
***********************************************************/
include 'dbc.php';
$err = array();
foreach($_GET as $key => $value) {
$get[$key] = filter($value); //get variables are filtered.
}
if ($_POST['doLogin']=='Login')
{
foreach($_POST as $key => $value) {
$data[$key] = filter($value); // post variables are filtered
}
$user_email = $data['usr_email'];
$pass = $data['pwd'];
if (strpos($user_email,'@') === false) {
$user_cond = "user_name='$user_email'";
} else {
$user_cond = "user_email='$user_email'";
}
$result = $mysqli->query("SELECT `id`,`pwd`,`full_name`,`approved`,`user_level` FROM users WHERE
$user_cond
AND `banned` = '0'
") or die ($mysqli->error);
$num = $result->num_rows;
// Match row found with more than 1 results - the user is authenticated.
if ( $num > 0 ) {
list($id,$pwd,$full_name,$approved,$user_level) = $result->fetch_row();
if(!$approved) {
//$msg = urlencode("Account not activated. Please check your email for activation code");
$err[] = "Account not activated. Please check your email for activation code";
//header("Location: login.php?msg=$msg");
//exit();
}
//check against salt
if ($pwd === PwdHash($pass,substr($pwd,0,9))) {
if(empty($err)){
// this sets session and logs user in
session_start();
session_regenerate_id (true); //prevent against session fixation attacks.
// this sets variables in the session
$_SESSION['user_id']= $id;
$_SESSION['user_name'] = $full_name;
$_SESSION['user_level'] = $user_level;
$_SESSION['HTTP_USER_AGENT'] = md5($_SERVER['HTTP_USER_AGENT']);
//update the timestamp and key for cookie
$stamp = time();
$ckey = GenKey();
$mysqli->query("update users set `ctime`='$stamp', `ckey` = '$ckey' where id='$id'") or die($mysqli->error);
//set a cookie
if(isset($_POST['remember'])){
setcookie("user_id", $_SESSION['user_id'], time()+60*60*24*COOKIE_TIME_OUT, "/");
setcookie("user_key", sha1($ckey), time()+60*60*24*COOKIE_TIME_OUT, "/");
setcookie("user_name",$_SESSION['user_name'], time()+60*60*24*COOKIE_TIME_OUT, "/");
}
header("Location: myaccount.php");
}
}
else
{
//$msg = urlencode("Invalid Login. Please try again with correct user email and password. ");
$err[] = "Invalid Login. Please try again with correct user email and password.";
//header("Location: login.php?msg=$msg");
}
} else {
$err[] = "Error - Invalid login. No such user exists";
}
}
?>
<html>
<head>
<title>Members Login</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<script language="JavaScript" type="text/javascript" src="js/jquery-1.3.2.min.js"></script>
<script language="JavaScript" type="text/javascript" src="js/jquery.validate.js"></script>
<script>
$(document).ready(function(){
$("#logForm").validate();
});
</script>
<link href="styles.css" rel="stylesheet" type="text/css">
</head>
<body>
<table width="100%" border="0" cellspacing="0" cellpadding="5" class="main">
<tr>
<td colspan="3"> </td>
</tr>
<tr>
<td width="160" valign="top"><p> </p>
<p> </p>
<p> </p>
<p> </p>
<p> </p></td>
<td width="732" valign="top"><p> </p>
<h3 class="titlehdr">Login Users
</h3>
<p>
<?php
/******************** ERROR MESSAGES*************************************************
This code is to show error messages
**************************************************************************/
if(!empty($err)) {
echo "<div class=\"msg\">";
foreach ($err as $e) {
echo "$e <br>";
}
echo "</div>";
}
/******************************* END ********************************/
?></p>
<form action="login.php" method="post" name="logForm" id="logForm" >
<table width="65%" border="0" cellpadding="4" cellspacing="4" class="loginform">
<tr>
<td colspan="2"> </td>
</tr>
<tr>
<td width="28%">Username / Email</td>
<td width="72%"><input name="usr_email" type="text" class="required" id="txtbox" size="25"></td>
</tr>
<tr>
<td>Password</td>
<td><input name="pwd" type="password" class="required password" id="txtbox" size="25"></td>
</tr>
<tr>
<td colspan="2"><div align="center">
<input name="remember" type="checkbox" id="remember" value="1">
Remember me</div></td>
</tr>
<tr>
<td colspan="2"> <div align="center">
<p>
<input name="doLogin" type="submit" id="doLogin3" value="Login">
</p>
<p><a href="register.php">Register Free</a><font color="#FF6600">
|</font> <a href="forgot.php">Forgot Password</a> <font color="#FF6600">
</font></p>
<p><span style="font: normal 9px verdana">Powered by <a href="http://php-login-script.com">PHP
Login Script v2.3</a></span></p>
</div></td>
</tr>
</table>
<div align="center"></div>
<p align="center"> </p>
</form>
<p> </p>
</td>
<td width="196" valign="top"> </td>
</tr>
<tr>
<td colspan="3"> </td>
</tr>
</table>
</body>
</html>您的$link变量未传递到函数中，因此您需要查看variable scoping。因此，您需要将$link传递到函数中，例如function filter($link, $data) {，然后像$cookie_user_id = filter($link, $_COOKIE['user_id']);一样调用它。 logout()功能和使用$link的所有其他功能相同。
您正在使用
global $db;
在您的数据库功能中。但是在代码的前面，您这样做：
$link = new mysqli(DB_HOST, DB_USER, DB_PASS) or die("Couldn't make connection.");
$db = $link->select_db(DB_NAME) or die("Couldn't select database");
select_db()返回一个布尔值。 $link是您的数据库连接，而不是$db。