有人可以告诉我为什么我的代码正在运行。即使我已经注释了变量username，email，password，password2

由 发布于 
//let username = document.getElementById('username');
//let email = document.getElementById('email');
//let password = document.getElementById('password');
//let password2 = document.getElementById('password2');


function check(arr) {
    arr.forEach((input) => {
        console.log(input);
    })
}
// Addeventlisteners
document.getElementById('submit').addEventListener('click', (e) => {
    e.preventDefault();

    check([username, email, password, password2]);


})

<!DOCTYPE html>
<html lang="">

<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="style.css">
    <title>Form Validation</title>
</head>

<body>
    <div class="container">
        <h1>Register with us</h1>
        <form action="">
            <div class="row">
                <label for="">Username</label>
                <input id="username" type="text" placeholder="Enter username">
                <small>Error message</small>
            </div>
            <div class="row">
                <label for="">Email</label>
                <input id="email" type="text" placeholder="Enter email">
                <small>Error message</small>
            </div>
            <div class="row">
                <label for="">Password</label>
                <input id="password" type="password" placeholder="Enter password">
                <small>Error message</small>
            </div>
            <div class="row">
                <label for="">Confirm Password</label>
                <input type="password" id="password2" placeholder="Enter password again">
                <small>Error message</small>
            </div>
            <button id="submit">Submit</button>
        </form>
    </div>


    <script src="app.js">
    </script>
</body></html>

output when i clicked the submit button

**我什至清除了我的缓存，但随后显示了输入标签。有人可以帮我吗，我找不到解决方案。这是我第一次在这里问问题，所以我真的不知道如何发布问题**