如何在Swift中将NSObject类对象转换为JSON?

本文介绍了如何在Swift中将NSObject类对象转换为JSON?的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我有

var contacts : [ContactsModel] = []

和

class ContactsModel: NSObject { var contactEmail : String? var contactName : String? var contactNumber : String? var recordId : Int32? var modifiedDate : String? }

现在在联系人中，我有6个值，例如

Now in contacts I'm having 6 values like

现在我想将联系人转换为JSON怎么办?

Now i want to convert contacts into JSON how can i ?

我尝试了

var jsonData: NSData? do { jsonData = try NSJSONSerialization.dataWithJSONObject(contacts, options:NSJSONWritingOptions.PrettyPrinted) } catch { jsonData = nil } let jsonDataLength = "\(jsonData!.length)"

但是它使应用程序崩溃了.

But it crashes the app.

我的问题是手动将其一一转换为字典，这非常耗时，需要花费5分钟以上的时间才能记录6000条记录，所以我不想直接将模型转换为JSON并发送到服务器.

My issue is with manually converting in to a Dictionary one by one very time consuming it takes more than 5 minutes for 6000 records, So instead of that i want to convert directly model into JSON and send to server.

推荐答案

您的自定义对象无法直接转换为JSON. NSJSONSerialization类参考说:

Your custom object can't be converted to JSON directly. NSJSONSerialization Class Reference says:

可能转换为JSON的对象必须具有以下属性:

An object that may be converted to JSON must have the following properties:

• 顶级对象是NSArray或NSDictionary.

• The top level object is an NSArray or NSDictionary.

所有对象都是NSString，NSNumber，NSArray，NSDictionary或NSNull的实例.

All objects are instances of NSString, NSNumber, NSArray, NSDictionary, or NSNull.

所有字典键都是NSString的实例.

All dictionary keys are instances of NSString.

数字不是NaN或无穷大.

Numbers are not NaN or infinity.

您可以手动将对象转换为Dictionary，也可以使用 SwiftyJSON ， JSONModel 或斗篷.

You might convert your object to a Dictionary manually or use some libraries like SwiftyJSON, JSONModel or Mantle.

编辑:当前，在4.0及更高版本中，您可以使用Codable协议轻松地将对象转换为JSON.这是本机解决方案，不需要第三方库.请参阅将JSON与自定义类型一起使用苹果公司的文件.

Edit: Currently, with swift 4.0+, you can use Codable protocol to easily convert your objects to JSON. It's a native solution, no third party library needed. See Using JSON with Custom Types document from Apple.