我最近尝试将ajax实现到我网站的登录功能中。 它在普通PHP中工作良好，但当我发出ajax请求时，响应是一个HTML代码块，这是我一生中从未见过的。 下面是我的代码:

    $(document).ready(function(){

    function Message(color, text){
        $("#errorMSG span").text(text);
        $("#errorMSG").slideDown();
        $("#errorMSG").css("background-color",color);
    }

    function DissmissMessage(){
        $("#errorMSG").slideUp();
    }

    $("#loginSubmit").on('click', function(){
        var email = $("#loginEmail").val();
        var password = $("#loginPassword").val();

        if(email == ""){
            Message('red', 'Please enter your email');
        }else if(password == ""){
            Message('red', 'Please enter your password');
        }else{
            DissmissMessage();
            $.ajax({
                url: './includes/functions.php',
                method: 'POST',
                data:{
                    signup : 1,
                    email : email,
                    password : password
                },
                success: function(data){
                    if(data){
                        Message('green', 'Login Success.');
                        console.log(data);
                    }else{
                        
                        Message('red', 'Wrong password or email.');
                        console.log(data);
                    }
            },
        });
        }
    });
});

PHP部分:

if(isset($_POST['login'])){

    if(!$_POST['email']){
        $loginError = "Please enter your email.";
    }else{
        $email = ValidatedForm($_POST['email']);

        if(!$_POST['password']){
            $loginError ="Please enter your password.";
        }else{
            $password = ValidatedForm($_POST['password']);
            
        }

    }
    

    $query = "SELECT email, password, fullname, permission FROM users WHERE email = '$email'";

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

    if(mysqli_num_rows($result) > 0){

            while($row = mysqli_fetch_assoc($result)){

                $hashedPassword = $row['password'];
                $email = $row['email'];
                $name = $row['fullname'];
                $permission = $row['permission'];
            }

            if(password_verify($password, $hashedPassword)){
                //session_start();
                //setcookie('email', $email, time() + (86400 * 30), "/"); // 86400 = 1 day

                $_SESSION['email']=$email;
                $_SESSION['name']=$name;
                $_SESSION['permission']=$permission;
                echo 1;
            }
    }else{
            $loginError ="Wrong email or password.";
            echo 0;
    }

}

这是我的HTML表单:

<h1>Log in</h1>
    <form action = "<?php echo htmlspecialchars($_SERVER['PHP_SELF']); ?>" method = 'post' id="regform">
            <span>Email:</span><br>
            <input type="text" name="email" id="loginEmail"><br>
            <span>Password:</span><br>
            <input type="password" name="password" id="loginPassword"><br>

            <span style="position:relative; background-color: red; display: inline-block; border-radius: 100px;"> <?php echo $loginError ?></span>

            <br><br>
                <input type="button" name="login" value="Log in" id="loginSubmit">
    </form>

而且，我得到的响应是这个HTML块:

    <br />
<font size='1'><table class='xdebug-error xe-notice' dir='ltr' border='1' cellspacing='0' cellpadding='1'>
<tr><th align='left' bgcolor='#f57900' colspan="5"><span style='background-color: #cc0000; color: #fce94f; font-size: x-large;'>( ! )</span> Notice: Undefined index: fullname in E:\Programs\wamp64\www\CountDown\includes\functions.php on line <i>32</i></th></tr>
<tr><th align='left' bgcolor='#e9b96e' colspan='5'>Call Stack</th></tr>
<tr><th align='center' bgcolor='#eeeeec'>#</th><th align='left' bgcolor='#eeeeec'>Time</th><th align='left' bgcolor='#eeeeec'>Memory</th><th align='left' bgcolor='#eeeeec'>Function</th><th align='left' bgcolor='#eeeeec'>Location</th></tr>
<tr><td bgcolor='#eeeeec' align='center'>1</td><td bgcolor='#eeeeec' align='center'>0.0008</td><td bgcolor='#eeeeec' align='right'>263816</td><td bgcolor='#eeeeec'>{main}(  )</td><td title='E:\Programs\wamp64\www\CountDown\includes\functions.php' bgcolor='#eeeeec'>...\functions.php<b>:</b>0</td></tr>
</table></font>
<br />
<font size='1'><table class='xdebug-error xe-notice' dir='ltr' border='1' cellspacing='0' cellpadding='1'>
<tr><th align='left' bgcolor='#f57900' colspan="5"><span style='background-color: #cc0000; color: #fce94f; font-size: x-large;'>( ! )</span> Notice: Undefined variable: conn in E:\Programs\wamp64\www\CountDown\includes\functions.php on line <i>40</i></th></tr>
<tr><th align='left' bgcolor='#e9b96e' colspan='5'>Call Stack</th></tr>
<tr><th align='center' bgcolor='#eeeeec'>#</th><th align='left' bgcolor='#eeeeec'>Time</th><th align='left' bgcolor='#eeeeec'>Memory</th><th align='left' bgcolor='#eeeeec'>Function</th><th align='left' bgcolor='#eeeeec'>Location</th></tr>
<tr><td bgcolor='#eeeeec' align='center'>1</td><td bgcolor='#eeeeec' align='center'>0.0008</td><td bgcolor='#eeeeec' align='right'>263816</td><td bgcolor='#eeeeec'>{main}(  )</td><td title='E:\Programs\wamp64\www\CountDown\includes\functions.php' bgcolor='#eeeeec'>...\functions.php<b>:</b>0</td></tr>
</table></font>
<br />
<font size='1'><table class='xdebug-error xe-warning' dir='ltr' border='1' cellspacing='0' cellpadding='1'>
<tr><th align='left' bgcolor='#f57900' colspan="5"><span style='background-color: #cc0000; color: #fce94f; font-size: x-large;'>( ! )</span> Warning: mysqli_query() expects parameter 1 to be mysqli, null given in E:\Programs\wamp64\www\CountDown\includes\functions.php on line <i>40</i></th></tr>
<tr><th align='left' bgcolor='#e9b96e' colspan='5'>Call Stack</th></tr>
<tr><th align='center' bgcolor='#eeeeec'>#</th><th align='left' bgcolor='#eeeeec'>Time</th><th align='left' bgcolor='#eeeeec'>Memory</th><th align='left' bgcolor='#eeeeec'>Function</th><th align='left' bgcolor='#eeeeec'>Location</th></tr>
<tr><td bgcolor='#eeeeec' align='center'>1</td><td bgcolor='#eeeeec' align='center'>0.0008</td><td bgcolor='#eeeeec' align='right'>263816</td><td bgcolor='#eeeeec'>{main}(  )</td><td title='E:\Programs\wamp64\www\CountDown\includes\functions.php' bgcolor='#eeeeec'>...\functions.php<b>:</b>0</td></tr>
<tr><td bgcolor='#eeeeec' align='center'>2</td><td bgcolor='#eeeeec' align='center'>0.0387</td><td bgcolor='#eeeeec' align='right'>266272</td><td bgcolor='#eeeeec'><a href='http://www.php.net/function.mysqli-query' target='_new'>mysqli_query</a>
(  )</td><td title='E:\Programs\wamp64\www\CountDown\includes\functions.php' bgcolor='#eeeeec'>...\functions.php<b>:</b>40</td></tr>
</table></font>
<br />
<font size='1'><table class='xdebug-error xe-notice' dir='ltr' border='1' cellspacing='0' cellpadding='1'>
<tr><th align='left' bgcolor='#f57900' colspan="5"><span style='background-color: #cc0000; color: #fce94f; font-size: x-large;'>( ! )</span> Notice:  SELECT email FROM users WHERE email =''  in E:\Programs\wamp64\www\CountDown\includes\functions.php on line <i>40</i></th></tr>
<tr><th align='left' bgcolor='#e9b96e' colspan='5'>Call Stack</th></tr>
<tr><th align='center' bgcolor='#eeeeec'>#</th><th align='left' bgcolor='#eeeeec'>Time</th><th align='left' bgcolor='#eeeeec'>Memory</th><th align='left' bgcolor='#eeeeec'>Function</th><th align='left' bgcolor='#eeeeec'>Location</th></tr>
<tr><td bgcolor='#eeeeec' align='center'>1</td><td bgcolor='#eeeeec' align='center'>0.0008</td><td bgcolor='#eeeeec' align='right'>263816</td><td bgcolor='#eeeeec'>{main}(  )</td><td title='E:\Programs\wamp64\www\CountDown\includes\functions.php' bgcolor='#eeeeec'>...\functions.php<b>:</b>0</td></tr>
<tr><td bgcolor='#eeeeec' align='center'>2</td><td bgcolor='#eeeeec' align='center'>0.0668</td><td bgcolor='#eeeeec' align='right'>266504</td><td bgcolor='#eeeeec'><a href='http://www.php.net/function.trigger-error' target='_new'>trigger_error</a>
(  )</td><td title='E:\Programs\wamp64\www\CountDown\includes\functions.php' bgcolor='#eeeeec'>...\functions.php<b>:</b>40</td></tr>
</table></font>
<br />
<font size='1'><table class='xdebug-error xe-warning' dir='ltr' border='1' cellspacing='0' cellpadding='1'>
<tr><th align='left' bgcolor='#f57900' colspan="5"><span style='background-color: #cc0000; color: #fce94f; font-size: x-large;'>( ! )</span> Warning: mysqli_num_rows() expects parameter 1 to be mysqli_result, null given in E:\Programs\wamp64\www\CountDown\includes\functions.php on line <i>42</i></th></tr>
<tr><th align='left' bgcolor='#e9b96e' colspan='5'>Call Stack</th></tr>
<tr><th align='center' bgcolor='#eeeeec'>#</th><th align='left' bgcolor='#eeeeec'>Time</th><th align='left' bgcolor='#eeeeec'>Memory</th><th align='left' bgcolor='#eeeeec'>Function</th><th align='left' bgcolor='#eeeeec'>Location</th></tr>
<tr><td bgcolor='#eeeeec' align='center'>1</td><td bgcolor='#eeeeec' align='center'>0.0008</td><td bgcolor='#eeeeec' align='right'>263816</td><td bgcolor='#eeeeec'>{main}(  )</td><td title='E:\Programs\wamp64\www\CountDown\includes\functions.php' bgcolor='#eeeeec'>...\functions.php<b>:</b>0</td></tr>
<tr><td bgcolor='#eeeeec' align='center'>2</td><td bgcolor='#eeeeec' align='center'>0.0944</td><td bgcolor='#eeeeec' align='right'>266536</td><td bgcolor='#eeeeec'><a href='http://www.php.net/function.mysqli-num-rows' target='_new'>mysqli_num_rows</a>
(  )</td><td title='E:\Programs\wamp64\www\CountDown\includes\functions.php' bgcolor='#eeeeec'>...\functions.php<b>:</b>42</td></tr>
</table></font>