const firebaseConfig = {
  apiKey: "AvRJxhkVpSR8Lfb6JqZ1GE-jBfuY", // 您的 Firebase API key
  authDomain: "nodejsproject-d099d.firebaseapp.com",
  projectId: "nodejsproject-d099d",
  storageBucket: "nodejsproject-d099d.appspot.com",
  messagingSenderId: "620886577949",
  appId: "1:620886577949:web:bb7819e6cb71ffb05307f4",
  measurementId: "G-CKJW9DEX9H",
};

firebase.initializeApp(firebaseConfig);

let preview = document.querySelector("#preview");
preview.textContent = "這是預覽的值";

const myData = firebase.database().ref("myData");
let data = {
  store1: "American restaurant",
  store2: "Korean restaurant",
  store3: "Japanese restaurant",
  store4: "Taiwanese restaurant",
};
myData.set(data);
myData.on("value", function (snapshot) {
  preview.textContent = JSON.stringify(snapshot.val(), null, 3);
});