javascript - 为什么在 createUserWithEmailAndPassword 之后获取 uid 时 Firebase 返回未定义

Question

这个问题已经有答案了:

Paths must be non-empty strings and can't contain ".", "#", "$", "[", or "]" [duplicate] (1 个回答)

已关闭 4 年前。

我正在尝试将新注册的用户及其新创建的用户 UID 保存到数据库中。然而它返回未定义，我不知道为什么。这就是我所拥有的

function fb_signup(){
    firebase.auth().createUserWithEmailAndPassword(email, password)
    .then(function success(userData){
        var uid = userData.uid;
        var displayName = userData.displayName;
        var email = userData.email;
        var emailVerified = userData.emailVerified;
        var photoURL = userData.photoURL;
        var isAnonymous = userData.isAnonymous;
        var providerData = userData.providerData;
        $('#fbFormMessage').css({'display':'block','background-color':'#c9e9cc','color':'#347f3b'});
        document.getElementById("fbFormMessage").innerHTML = 'Welcome Your registration was successful.';
        console.log(uid + ' | ' + email + ' | ' + uName )
        saveNewUser(uid, email, uName);
        return false;
    })
    .catch(function failure(error) {
        var errorCode = error.code;
        var errorMessage = error.message;
        console.log(errorCode + " " + errorMessage);
        $('#fbFormMessage').css({'display':'block','background-color':'#FFEBEE','color':'#EF5350'});
        document.getElementById("fbFormMessage").innerHTML = 'The email address is already in use by another account';
    });
};




    function saveNewUser(a,b,c){
    console.log('4')
    var rootRef = firebase.database().ref();
    var storesRef = rootRef.child('/users/'); 
    var newStoreRef = storesRef.push();
    newStoreRef.set({
    uid: a,
    userName: c,
    email: b,
    });
    };

Answer 1

因为 createUserWithEmailAndPassword() 方法返回 UserCredential (而不是用户)，详见文档:https://firebase.google.com/docs/reference/js/firebase.auth.Auth#createUserWithEmailAndPassword

所以你应该这样做:

function fb_signup(){
    firebase.auth().createUserWithEmailAndPassword(email, password)
    .then(function success(userCredential){
        var userData = userCredential.user;
        var uid = userData.uid;
        ....