JSON Deserialize to list C#

Question

My JSON has this information:

[
 {
  "era_1":{"technology_cost":"10000"},
  "era_2":{"technology_cost":"15000"},
  "era_3":{"technology_cost":"20000"},
  "era_4":{"technology_cost":"25000"},
  "era_5":{"technology_cost":"30000"}
 }
]

I want to do:

EraData = JsonConvert.DeserializeObject<List<ClassEra>>(JSON);

Being ClassEra

public class ClassEra
{
    public string name { get; set; }
    public string technology_cost { get; set; }
}

And obviously it doesn't work.

I don't understand the type of data that is coming out of the deserializer.

By the way I'm using Newtonsoft.

You need to account for the `"era_X"` names. I reckon those are runtime-only names so use `JsonConvert.DeserializeObject>>(JSON);`. See as shown in [Deserializing JSON when key values are unknown](https://stackoverflow.com/a/24901245/3744182). — dbc, Oct 23 '22 at 17:51
At first glance, it looks like you are declaring your class wrongly. The JSON is a list of 1 object which then has multiple objects. — elfico, Oct 23 '22 at 17:53
@dbc i dont know the number of era_x that are coming so what sould i do? — Filipe, Oct 23 '22 at 17:55
@Filipe - I told you. Use `JsonConvert.DeserializeObject>>(JSON)`. The `era_X` names will be deserialized as the dictionary keys, the `{"technology_cost":"XX"}` objects as the dictionary values. Also you can remove `name` from `ClassEra`. — dbc, Oct 23 '22 at 17:57

score 1 · Answer 1 · answered Oct 23 '22 at 18:10

1

The json format is not what you are trying to capture as class object. Your targeted json should be :

[{"name":"era_1","technology_cost":"10000"},
{"name":"era_2","technology_cost":"15000"},
{"name":"era_3","technology_cost":"20000"},
{"name":"era_4","technology_cost":"25000"},
{"name":"era_5","technology_cost":"30000"}]

answered Oct 23 '22 at 18:10

JemHah

434
4
16

That is just how the data comes, cant do anything – Filipe Oct 23 '22 at 19:40

Pradeep Kumar · Accepted Answer · 2022-10-23T19:09:25.787

0

try this one

EraData  = JsonConvert.DeserializeObject<List<Dictionary<string, ClassEra>>>(JSON);

And class will be

    public class ClassEra
    {
        public string technology_cost { get; set; }
    }

Fetching details

I prefer to use dictionary because time complexity of fetching value is O(1) by key like dic[key]

//By this :- get complete dictionary
var dic = EraData[0]; //and iterate by foreach loop 
 
//by this you can get all technology cost:- 
var technology_cost = EraData.SelectMany(x => x.Values);

Screenshots

Dictionary

Technology Cost

edited Oct 23 '22 at 19:09

answered Oct 23 '22 at 18:05

Pradeep Kumar

1,193
1
9
21

1

How do i get the value of the class in the dictionary? – Filipe Oct 23 '22 at 18:19
By this :- get complete dictionary var dic = EraData[0]; and iterate by foreach loop – Pradeep Kumar Oct 23 '22 at 19:04
by this you can get all technology cost:- var technology_cost = EraData.SelectMany(x => x.Values); – Pradeep Kumar Oct 23 '22 at 19:04

score 0 · Answer 3 · answered Oct 23 '22 at 18:18

0

To expand a bit on what @Pradeep wrote, if you want to know the era name you could select it like this

var dict = JsonConvert.DeserializeObject<List<Dictionary<string, ClassEra>>>(json);

var eras = dict.SelectMany(x => x.Keys.Select(k => new ClassEra()
{
    Name = k,
    TechnologyCost = x[k].TechnologyCost
}));

public class ClassEra
{
    public string Name { get; set; }
    [JsonProperty("technology_cost")] public string TechnologyCost { get; set; }
}

answered Oct 23 '22 at 18:18

LLL

3,566
2
25
44

Thank you so much, i was tryind to what dbc and Pradeep said but couldnt get the "technology_cost" out. Is it because the _ is not supported? – Filipe Oct 23 '22 at 18:27
It's supported, it's just the structure was not the same as in your class. In C# the convention is to name things in `PascalCase` and not `snake_case`, that's why I changed it, but it still works with both. – LLL Oct 24 '22 at 08:21

JSON Deserialize to list C#

3 Answers3