使用领域和结果 JSON

Posted 2023-03-14

【中文标题】使用领域和结果 JSON

【英文标题】：Working with Realm and result JSON

【发布时间】：2017-08-15 06:51:25

【问题描述】：

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

'尝试在写入事务之外修改对象 - 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":"[e-mail]","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)")
    

【参考方案1】：

不要修改persons 对象并将其再次添加到领域。您看到的错误是因为您将人员添加到领域，然后在 for eachItem in data 的第二次迭代中再次对其进行编辑。 Persons 已在此迭代中添加到领域，您尝试在领域写入事务之外为其指定一个新名称。这就是您看到错误的原因。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)")
    

【讨论】：

谢谢@Yannick 工作完美:)

【参考方案2】：

如错误所示，您需要在写入中执行事务，

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)
    

第二种选择是构建一个对象，然后编写：

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，但这就是我们的想法。