如何使用Firebase验证用户在iOS上的电子邮件地址？

import FirebaseAuth

// 创建用户账号
Auth.auth().createUser(withEmail: email, password: password) { (authResult, error) in
    guard let user = authResult?.user, error == nil else {
        print(error?.localizedDescription)
        return
    }
    
    // 发送验证电子邮件
    user.sendEmailVerification { (error) in
        if let error = error {
            print(error.localizedDescription)
        } else {
            print("Verification email sent.")
        }
    }
}

import FirebaseAuth

// 检查用户电子邮件地址是否已验证
if let user = Auth.auth().currentUser {
    if user.isEmailVerified {
        print("Email is verified.")
    } else {
        print("Email is not verified.")
    }
}