登录PHP时连接失败

Question

我一点也不理解这段代码的问题！它确实起作用了，但现在它不起作用了。我无法登录到任何人都能看到和发布的‘个人资料页面’。

<?php
session_start(); 

$error=''; 
if (isset($_POST['submit'])) 
{
    if (empty($_POST['username']) || empty($_POST['password'])) 
    {
        $error = "Enter username & password";
    }
else {
    // Define $username and $password
    $username=$_POST['username'];
    $password=$_POST['password'];

    $connection = mysql_connect("localhost", "root", "");
    echo($connection);
    $username = stripslashes($username);
    $password = stripslashes($password);
    $username = mysql_real_escape_string($username);
    $password = mysql_real_escape_string($password);

    $db = mysql_select_db("Windsor", $connection);
        echo($db);      
        $sql = "SELECT * FROM PHP_Customer WHERE Email='$username' and Password='$password'";
        echo($sql);
        $result = mysql_query($sql);

            $count=mysql_num_rows($result);

            if ($count < 1) 
            {
                $error = "Username or Password is incorrect";
            }
            else
            {
                $_SESSION['user_login'] = $username; 
                header('location: profile.php');
                echo "hello world!"; // This is just for testing purposes

            }
        } 
mysql_close($connection); 
}

?>

正如我已经说过的，它确实起作用了，不管是什么原因，它似乎不再有效了。

Answer 1

Ok发现了一些问题。

1)语句中有一个小写的"AND“。它应该是：

 $sql = "SELECT * FROM PHP_Customer WHERE Email='$username' AND Password='$password'";

2)不要将mysql_select_db设置为变量并回显它。该行应为：

mysql_select_db("Windsor", $connection);

3)不要回显连接细节。

4)在您的mysql语句中添加一些错误检查。

脚本现在应该如下所示：

<?php
session_start(); 

$error=''; 
if (isset($_POST['submit'])) 
{
    if (empty($_POST['username']) || empty($_POST['password'])) 
    {
        $error = "Enter username & password";
    }
else {
    // Define $username and $password
    $username=$_POST['username'];
    $password=$_POST['password'];

    $connection = mysql_connect("localhost", "root", "") or die(mysql_error());
    $username = stripslashes($username);
    $password = stripslashes($password);
    $username = mysql_real_escape_string($username);
    $password = mysql_real_escape_string($password);

    mysql_select_db("Windsor", $connection) or die(mysql_error());      
        $sql = "SELECT * FROM PHP_Customer WHERE Email='$username' AND Password='$password'";
        $result = mysql_query($sql) or die(mysql_error());

            $count=mysql_num_rows($result);

            if ($count < 1) 
            {
                $error = "Username or Password is incorrect";
            }
            else
            {
                $_SESSION['user_login'] = $username; 
                header('location: profile.php');
                echo "hello world!"; // This is just for testing purposes

            }
        } 
mysql_close($connection); 
}

?>