PHP 登录表单不适用于 mysql

Question

<?php
if(array_key_exists("logIn",$_POST))
{
     $link = mysqli_connect("dbaddress", "dbname", "dbpassword", "dbuser");

    if(!$_POST['regno'])
    {
        $error .= "Please enter your registration number";
    }
    if(!$_POST['password'])
    {
        $error .= "Password is required!";
    }
    if($error!="")
    {
        echo "<p>There were errors in your forms!</p>".$error;
    }
    else
    {
                           $query = "SELECT * FROM `users` WHERE RegistrationNo = '".mysqli_real_escape_string($link, $_POST['regno'])."'";

                $result = mysqli_query($link, $query);

                $row = mysqli_fetch_array($result);

                if (isset($row)) {

                    $hashedPassword = md5(md5($row['id']).$_POST['password']);

                    if ($hashedPassword == $row['password']) {

                        $_SESSION['id'] = $row['id'];
                        header("Location: after_login.php");
                        } 
                    else {
           $error = "That email/password combination could not be found.";
                          }                   
                          } 
                    else {
            $error = "That email/password combination could not be found.";
                 }   
                }}
?>

    <form method="post">
<center><input type="text" placeholder="Enter Username" name="regno"      id="log_username" class="sidelog"/>
<input type="password"   placeholder="Enter Password" name="password"    id="real_pass" class="sidelog"/>
</br><button id="button_log" type="submit" name="logIn" > GO </button>    </center>
</form>

每当我填写并提交表单时，页面都会重新加载。 header 不起作用。我似乎无法弄清楚为什么。如果我将表单留空，则错误字符串会正确显示。我对密码使用了md5加密。我将数据库中 id 的 md5 与密码连接起来，然后 md5 加密了结果字符串。

Answer 1

试试这个可能对你有帮助，

     if ($hashedPassword == $row['password']) {
           $_SESSION['id'] = $row['id'];
           header("Location: after_login.php");
           die();
     }