Swift 3:Realm创建了额外的对象,而不是更新现有的对象

Question

在我的AppDelegate中

let realm = try! Realm()
    print("number of users")
    print(realm.objects(User.self).count)
    if !realm.objects(User.self).isEmpty{
        if realm.objects(User.self).first!.isLogged {
            User.current.setFromRealm(user: realm.objects(User.self).first!)
            let storyboard = UIStoryboard(name: "Main", bundle: nil)
            let viewController = storyboard.instantiateViewController(withIdentifier :"TabBar") as! CustomTabBarController
            self.window?.rootViewController = viewController
        }
    } else {
        try! realm.write { realm.add(User.current) }
    }

我只在应用程序中没有用户对象时才创建用户

由于这个答案,我以下面的方式更新我的对象

public func update(_ block: (() -> Void)) {
    let realm = try! Realm()
    try! realm.write(block)
}

但事实证明它创建了新的User对象.如何始终更新现有的而不是创建新对象？

请注意我使用,User.current因为我的对象是单例

登录和注销后,它会打印用户数= 2,这意味着更新现有用户会创建一个新用户

Answer 1

领域将为您检查对象是否存在.只用add和update.

// Create or update the object
try? realm.write {
   realm.add(self, update: true)
}     

文件:

 - parameter object: The object to be added to this Realm.
 - parameter update: If `true`, the Realm will try to find an existing copy of the object (with the same primary
                     key), and update it. Otherwise, the object will be added.