如何在 C# 中反序列化 json

Question

Hello I'm trying to deserialize the following json in c#:

{  
 "Labels":[  
    {  
       "DeviceID":9,
       "Disabled":false,
       "Id":0,
       "Internal":"1@CB_I_AllCloseCheck",
       "Label":"CB_I_AllCloseCheck",
       "MAddress":0,
       "Mask":2147483648,
       "ModuleID":4,
       "Offset":0,
       "Position":1,
       "SectionID":0,
       "Type":16
     }
   ]
 }

With the following code line:

Labels myDeserializedObjList = (Labels)JsonConvert.DeserializeObject(sub, typeof(Labels));

The string sub contains this json like a string. Where my class Labels is the following:

public class Labels
    {
        public string DeviceID { get; set; }
        public string Disabled { get; set; }
        public string IValue { get; set; }
        public string Id { get; set; }
        public string Internal { get; set; }
        public string Label { get; set; }
        public string MAddress { get; set; }
        public string Mask { get; set; }
        public string ModuleID { get; set; }
        public string Offset { get; set; }
        public string Position { get; set; }
        public string SectionID { get; set; }
        public string Type { get; set; }
    }

But the result of this operation is all my atributes equal to null. Anyone knows what I'm doing wrong?

Answer 1

At the moment your root object is just that: an object. It's not an array. Its only property (Labels) is an array.

You should add an extra "root object" class:

public class LabelsContainer
{
    public IList<Labels> Labels {get;set;}
}

And then deserialize to that:

var labelsContainer = Newtonsoft.Json.JsonConvert.DeserializeObject<LabelsContainer>(data);
var labels = labelsContainer?.Labels;

Answer 2

The JSON string shows an object with a Labels property that contains an array of labels. You need to try something like :

class LabelsDTO
{
    public Labels[] Labels{get;set;}
}

...

var dto = JsonConvert.DeserializeObject<LabelsDTO>(sub);

for (var label in dto.Labels)
{
...
}