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在用户成功登录后，我想导航到不同的页面并导出auth，但是当我这样做时，我得到Uncaught TypeError：Cannot read properties of null（阅读'addEventListener'）on the button，but when I remove the export auth and remove the import statement from profile.js I don't get the error. I'm only doing this for testing purposes.

index.html

<form>
            <div>
                <label for="email">Email:</label>
                <input type="text" name="email" id="email">
                <label for="password">Password:</label>
                <input type="password" name="password" id="password">
            </div>
        </form>
        <div>
            <button id="button">Login</button>
        </div>

字符串

index.js

// firebase configurations....

const auth = getAuth(app);
const button = document.getElementById("button");
function login() {
const email = document.getElementById("email").value;
const password = document.getElementById("password").value;

signInWithEmailAndPassword(auth, email, password)
    .then((userCredential) => {
        const user = userCredential.user;
        // Handle successful login here
    })
    .catch((error) => {
        // Handle login error
        alert("Invalid login credentials");
    });
}
button.addEventListener("click", login);

onAuthStateChanged(auth, (user) => {
    if (user) {
        console.log("Signed In");

        // user is signed in
        const uid = user.uid;

        button.removeEventListener("click", login); // remove event lister
        // navigate to next page
        window.location.href = "/profile.html";

    } 
})

export { auth }

型

profile.js

import { auth } from "./index.js";

console.log(auth);

型