Create JSON manually

Question

i have a JSON which can for example look like this:

{
   "value":[
      {
         "Name":"Nik",
         "Age":"17",
         "Country":"Germany",
      },
      {
         "Name":"Tom",
         "Age":"20",
         "Country":"Russia",
      },
      {
         "Name":"Sila",
         "Age":"12",
         "Country":"Switzerland",

      }
   ]
}

The Keys of the properties like "Name" and "Age" are dynamic and can vary. The JSON could also look like this:

{
   "value":[
      {
         "Prename":"Nik",
         "Age":"17",
         "Country":"Germany"
         "Car":"Merc"
      },
      {
         "Prename":"Nik",
         "Age":"20",
         "Country":"Russia"
         "Car":"BMW"
      },
      {
         "Prename":"Nik",
         "Age":"12",
         "Country":"Switzerland",
         "Car":"Audi"
      }
   ]
}

The important thing is the strcuture, this is what i want to build manually with Newtonsoft.Json.

This is my current attempt:

var jArray = new JArray();
jArray.Add("Name");
jArray.Add("Nikola");

jArray.Add("Age");
jArray.Add("17");

jArray.Add("Country");
jArray.Add("Germany");

JObject o = new JObject();
o["Value"] = jArray;

string json = o.ToString();

Result:

{
  "Value": [
    "Name",
    "Nikola",
    "Age",
    "17",
    "Country",
    "Germany"
  ]
}

I tried to solve it with this example from the newtonsoft Website, but as you can see it's really poor explained.

Wouldn't it be easier to paste the JSON into Visual Studio, have it auto-generate a class that you can then fill and serialize at runtime without having to know anything about JSON's nitty gritty? — , Apr 07 '21 at 10:39
you need to add Jobjects to your array, and each object, you add properties — Keith Nicholas, Apr 07 '21 at 10:40
@MickyD: No need for a class here - just `var obj = new { value = new[] { Name = "Nik", Age = "12", Country = "Germany" } };` etc would be enough. If the OP wants to parse and then use the JSON, then using a class would make sense (although I'd probably just write it manually - it'll be trivial) but just for production, anonymous types are really useful. — Jon Skeet, Apr 07 '21 at 10:42
@MickyD the thing is, I get data, which can vary from amount type. So it is not given for me that i always have a "Name" Key. I have to get the data and then build the JSON structure i provideded above manually. I didn't mention this, because i thought i would be out of the frame. — Nikola Mitrovic, Apr 07 '21 at 10:44
@NikolaMitrovic: It sounds like there's quite a lot of context which is missing then... all we can really suggest is "use `JObject` to represent each object". With more information in the question, we're likely to be able to help you more. — Jon Skeet, Apr 07 '21 at 10:48
We still have no idea how you're receiving the information, which still makes it very hard to even imagine what a useful answer would look like, beyond the very general "use JObject". — Jon Skeet, Apr 07 '21 at 10:56
It seems you are stuck on using `JObject`, but with context I feel like this could be solved with a much more appropriate solution. For example, the keys and values of your individual items could be taken from a Dictionary, that way things are still dynamic and you get to use a concrete class. — DavidG, Apr 07 '21 at 10:57
@JonSkeet I wrote a new question were i am really specific, i thought to live this question as it is, because it still might help other people. https://stackoverflow.com/questions/66985340/transform-excel-data-into-specific-json-format — Nikola Mitrovic, Apr 07 '21 at 11:41

Keith Nicholas · Accepted Answer · 2021-04-07T10:58:57.247

You need to add JObject into the array like so. I imagine you you will have to add whatever condition properties (or other nested objects) you want

var jArray = new JArray();
var nik = new JObject();
nik["Name"] = "nik";
nik["Age"] = "17";
nik["Country"] ="Germany";

jArray.Add(nik);
JObject o = new JObject();
o["Value"] = jArray;

string json = o.ToString();

depending on the exact nature of your dynamic content, you can use intializer code like

    var jArray = new JArray
    {
        new JObject {["Name"] = "nik", ["Age"] = "17", ["Country"] = "Germany"},
        new JObject {["Name"] = "bob", ["Age"] = "32", ["Country"] = "New Zealand"}
    };
    var o = new JObject {["Value"] = jArray};

godot · Answer 2 · 2021-04-07T10:55:59.987

1

If you want to construct your object dynamically you can use dictionary:

var jsonObj = new Dictionary<string, List<Dictionary<string, string>>>
{
    {
        "Value", new List<Dictionary<string, string>>
        {
            new Dictionary<string, string>
            {
                {"Prename", "Nik"},
                {"Age", "17"},
                {"Country", "Germany"},
                {"Car", "Merc"}
            },
            new Dictionary<string, string>
            {
                {"Prename", "Nik"},
                {"Age", "20"},
                {"Country", "Russia"},
                {"Car", "BMW"}
            },
            new Dictionary<string, string>
            {
                {"Prename", "Nik"},
                {"Age", "12"},
                {"Country", "Switzerland"},
                {"Car", "Audi"}
            }
        }
    }
};
var json = JsonConvert.SerializeObject(jsonObj);
Console.WriteLine(json);

edited Apr 07 '21 at 10:55

answered Apr 07 '21 at 10:45

godot

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this works a little bit, but if his structure is dynamic, then this won't work – Keith Nicholas Apr 07 '21 at 10:47
@KeithNicholas this is exactly the problem! My strcuture is dynamic. i will edit my question and mention this. – Nikola Mitrovic Apr 07 '21 at 10:49
thanks for you remark, I am going to update my answer – godot Apr 07 '21 at 10:50

score 1 · Answer 3 · answered Apr 07 '21 at 10:50

You could consider creating it from an anonymous object instead, like this:

JObject o = JObject.FromObject(new
{
    value = new [] {
        new {
            Name = "Nik",
            Age = "17",
            Country = "Germany"
        },

        new {
            Name = "Nik1",
            Age = "18",
            Country = "Austria"
        },
    }
});

string json = o.ToString();

It produces this result:

{
  "value": [
    {
      "Name": "Nik",
      "Age": "17",
      "Country": "Germany"
    },
    {
      "Name": "Nik1",
      "Age": "18",
      "Country": "Austria"
    }
  ]
}

score 1 · Answer 4 · answered Apr 07 '21 at 11:05

I believe the exact structure you are looking to achieve is:

    //New Json Array
    var manualJSON = new JArray();

    //Add Nik
    var NIK = new JObject();
    NIK["Name"] = "Nik";
    NIK["Age"] = "17";
    NIK["Country"] = "Germany";

    //Add Tom
    var Tom = new JObject();
    Tom["Name"] = "Tom";
    Tom["Age"] = "20";
    Tom["Country"] = "Russia";
    
    //Add People to Json Array
    manualJSON.Add(Tom);
    manualJSON.Add(NIK);

    //Pass your json to a new object to print
    JObject o = new JObject();
    o["value"] = manualJSON;

    //Live Testing
    string json = o.ToString();
    File.WriteAllText("test.txt", json);
    Process.Start("test.txt");

Create JSON manually

4 Answers4