使用 JS 错误消息登录 PHP

我正在用PHP和JS创建一个登录脚本。我想在我的表单中有不同的错误消息，但不幸的是，并非一切都正常。例如，检查是否有这样的用户运行良好，但是如果我输入正确的电子邮件和不正确的密码，我将被重定向到profile.php？u=%3Cbr%20/%3E%3Cb%3ENotice%3C/（...）。我哪里犯了错误？

登录.php

if(isset($_POST["e_l"])){
    include_once("db/db_fns.php");
    $e = mysqli_real_escape_string($db_conx, $_POST['e_l']);
    $p = $_POST['p_l'];
    $ip = preg_replace('#[^0-9.]#', '', getenv('REMOTE_ADDR'));
    if($e == "" || $p == ""){
        $message = preg_replace('/['/_| -]+/', '', 'loginfailed');
        echo $message;
        exit();
    } else {
        $sql = "SELECT id, username, password, activated FROM users WHERE email='$e' LIMIT 1";
        $query = mysqli_query($db_conx, $sql);
        $row = mysqli_fetch_row($query);
        $activated = $row['activated'];
        $number = mysqli_num_rows($query);  
        if ($number <=0){
            $message = preg_replace('/['/_| -]+/', '', 'nouser');
            echo $message;
            exit();
        } else {
            if ($activated = '0') {
                $message = preg_replace('/['/_| -]+/', '', 'noactiv');
                echo $message;
                exit ();
            } else {
                $db_id = $row[0];
                $db_username = $row[1];
                $db_pass_str = $row[2];
                if (password_verify ($p, $db_pass_str)) {
                    $_SESSION['userid'] = $db_id;
                    $_SESSION['username'] = $db_username;
                    $_SESSION['password'] = $db_pass_str;
                    setcookie("id", $db_id, strtotime( '+30 days' ), "/", "", "", TRUE);
                    setcookie("user", $db_username, strtotime( '+30 days' ), "/", "", "", TRUE);
                    setcookie("pass", $db_pass_str, strtotime( '+30 days' ), "/", "", "", TRUE); 
                    $sql = "UPDATE users SET ip='$ip', lastlogin=now() WHERE username='$db_username' LIMIT 1";
                    $query = mysqli_query($db_conx, $sql);
                    echo $db_username;
                    exit();
                } else{
                    $message = preg_replace('/['/_| -]+/', '', 'loginfailed');
                    echo $message;
                    exit();
                } 
            }
        }
    }
    exit();
}

登录.js

function login(){
    var e_l = _("email_l").value;
    var p_l = _("password_l").value;
    if(e_l == "" || p_l == ""){
        _("status_l").innerHTML = '<div class="message_b"><img src="images/error.gif"/> Fill out all of the form data</div>';
    } else {
        _("loginbtn").style.display = "none";
        _("status_l").innerHTML = '<img src="images/wait.gif"/>';
        var ajax = ajaxObj("POST", "login.php");
        ajax.onreadystatechange = function() {
            if(ajaxReturn(ajax) == true) {
                if (ajax.responseText.trim() == "nouser"){
                    _("status_l").innerHTML = '<div class="message_b"><img src="images/error.gif"/> Wrong username</div>';
                    _("loginbtn").style.display = "block";
                }  else if (ajax.responseText.trim() == "noactiv"){
                    _("status_l").innerHTML = '<div class="message_b"><img src="images/error.gif"/> Your account is no active</div>';
                    _("loginbtn").style.display = "block";
                } else if (ajax.responseText.trim() == "loginfailed"){
                    _("status_l").innerHTML = '<div class="message_b"><img src="images/error.gif"/> Login unsuccessful, please try again</div>';
                    _("loginbtn").style.display = "block";
                } else {
                    window.location = "profile.php?u="+ajax.responseText;
                }
            }
        }
        ajax.send("e_l="+e_l+"&p_l="+p_l);
    }
}