Question

我是新手，我正在尝试在我的项目中使用Realm。在这里，我试图解析JSON并使用领域保存它。当我试图循环结果数组时发生错误

'尝试修改写事务之外的对象 - 首先在RLMRealm实例上调用beginwritetransaction'

这是JSON结果：

{"data":[{"id":1,"parent_id":0,"name":"JenniferMaenle","title":"Ms","phone":"","address":"Toled, ohio","email":"jlmaenle@aol.com","image":"44381525_2017.jpg","relation_id":5,"created_at":null,"updated_at":"2017-08-10 02:30:05"},{"id":2, "parent_id":1,"name":"Khadeeja","title":"","phone":"","address":"","email":"","image":"Khadeeja_2017-07-17.jpg","relation_id":2,"created_at":null,"updated_at":"2017-07-17 08:3:12"}]}

我正在尝试解析JSON并将其保存在Realm数据库中。这是我的尝试：

class Person: Object {

dynamic var name = ""
dynamic var title = ""
dynamic var address = ""

}

override func viewDidLoad() {
    super.viewDidLoad()
    self.add()

}

func add(){

   guard let data = dataFromFile("ServerData") else { return }

    let persons = Person()

    do {

        if let json = try JSONSerialization.jsonObject(with: data) as? [String: AnyObject] {

            if let data = json["data"] as? [[String:AnyObject]]{

                for eachItem in data{
                    persons.name = eachItem["name"] as! String
                    persons.title = eachItem["title"] as! String
                    persons.address = eachItem["address"] as! String

                    try! realm.write {
                        realm.add(persons)
                    }
                }

            }
        }
    } catch {

        print("Error deserializing JSON: \(error)")
    }
}

Answer 1

如错误所示，您需要在写入中预先形成事务

一种选择是单独写每个人：

for eachItem in data{
    let person = Person()
    person.name = eachItem["name"] as! String
    person.title = eachItem["title"] as! String
    person.address = eachItem["address"] as! String

    try! realm.write {
         realm.add(person)
    }
}

第二个选项是构建一个对象然后写：

for eachItem in data{
    let person = Person();
    person.name = eachItem["name"] as! String
    person.title = eachItem["title"] as! String
    person.address = eachItem["address"] as! String
    persons.add(person)
}
try! realm.write {
    realm. append(persons)
}

您可能需要对此进行一些更改，但这是个主意。

Answer 2

请勿修改persons对象并再次将其添加到域中。您看到的错误是因为您将人员添加到领域，然后再次在for eachItem in data的第二次迭代中对其进行编辑。在此迭代中，Persons已添加到领域中，并且您尝试在领域写入事务之外为其指定新名称。这就是你看错的原因。最好为每个人创建一个新对象。

func add(){
    guard let data = dataFromFile("ServerData") else { return }

    do {
        if let json = try JSONSerialization.jsonObject(with: data) as? [String: AnyObject] {
            if let data = json["data"] as? [[String:AnyObject]]{
                for eachItem in data{
                    let persons = Person()
                    persons.name = eachItem["name"] as! String
                    persons.title = eachItem["title"] as! String
                    persons.address = eachItem["address"] as! String

                    try! realm.write {
                        realm.add(persons)
                    }
                }

            }
        }
    } catch {
        print("Error deserializing JSON: \(error)")
    }
}

使用Realm和结果JSON

2 个答案: