Question

我只是乱搞PHP和MySql来学习东西......直到现在一切都很好，但现在我找不到任何解决方案。基础是一个非常简单的登录系统。现在我试图从名为'login'的数据库中读取用户名和密码，其中包含'userTBL'表和字段'username'和'password'。

 <?php 
    session_start();

    mysql_connect ('localhost', 'root', 'root') or die('NO MYSQL CONNECTION!');
    mysql_select_db('login');  

    if ($_GET['login']) {
        $username = ($_POST['username']);
        $password = ($_POST['password']);

        $tmp = mysql_query("SELECT * FROM `user`");

        $data = mysql_fetch_array($tmp);

        if($tmp) {
            echo 'FULL<br />';
        } else {
            echo 'EMPTY<br />';
        }

        $_SESSION['username'] = $data['username'];
        $_SESSION['password'] = $data['password'];

         if ($username == $_SESSION['username'] && $password == $_SESSION['password']) {
             $_SESSION['loggedin'] = true;
             header("Location: protected.php");
             exit;
         } else echo "Wrong details!<br />";
    }
    if ($_SESSION['loggedin'] == true) {
        header("Location: protected.php"); 
    }
?>

似乎数据库不会返回任何内容，但为什么？！？！

感谢您的帮助！

Answer 1

您提到您的表名为'userTBL'，但您正在查询表'user'。将您的查询更改为：$ tmp = mysql_query（“SELECT * FROM userTBL WHERE username = {$ username} AND password = {$ password}”）; 'WHERE'子句将确保查询仅返回与键入表单的用户名和密码匹配的数据。

Answer 2

    <?php 
    session_start();

    mysql_connect ('localhost', 'root', 'root') or die('NO MYSQL CONNECTION!');
    mysql_select_db('login');  

    if ($_GET['login']) {
        $username = htmlspecialchars($_POST['username']);
        $password = htmlspecialchars($_POST['password']);

        $tmp = mysql_query('SELECT * FROM `userTBL` WHERE `user` = "'.$username.'"');

        while ($data = mysql_fetch_array($tmp))
        {
            $_SESSION['username'] = $username;
            $_SESSION['password'] = $data['password'];

         if ($password == $_SESSION['password']) {
             $_SESSION['loggedin'] = true;
             header("Location: protected.php");
             exit;
         } else echo "Wrong details!<br />";
         }
    }
    if ($_SESSION['loggedin'] == true) {
        header("Location: protected.php"); 
    }
?>

另外：使用salt + hash将密码存储在数据库中。

MySql不返回任何内容

2 个答案: