Convert JSON array into another structure

Question

I am looking for a solution where I can convert the JSON structure with C#. Currently, I am trying to convert this JSON structure using the Newtonsoft library but I'm not finding any solution.

Below JSON needs to be converted :

[
    [
        {
            "FieldName": "Id",
            "Value": 1234
        },
        {
            "FieldName": "FieldName1",
            "Value": 2722
        },
        {
            "FieldName": "FieldName2",
            "Value": "2022-06-21T13:03:11.5958542Z"
        },
        {
            "FieldName": "FieldName3",
            "Value": "XYZ"
        }
    ]
]

Required JSON structure from above JSON :

[
    {
        "Id": 1234,
        "FieldName1" : 2722,
        "FieldName2" : "2022-06-21T13:03:11.5958542Z",
        "FieldName3" : "XYZ"
    }
]

Answer 1

You have to iterate over your inner array.

A single JObject has to be created and in the loop filled with the data from your input array.

The data type of the value has to be checked: int.TryParse
In the case of boolean values, the if condition has to be extended.

public void Transform()
{
    var data = "[ [ { \"FieldName\": \"Id\", \"Value\": 1234 }, { \"FieldName\": \"FieldName1\", \"Value\": 2722 }, { \"FieldName\": \"FieldName2\", \"Value\": \"2022-06-21T13:03:11.5958542Z\" }, { \"FieldName\": \"FieldName3\", \"Value\": \"XYZ\" } ] ]";

    var input = JArray.Parse(data);
    var inputFirst = input[0] as JArray;

    var outputItem = new JObject();

    foreach (JObject item in inputFirst)
    {
        var fieldName = item["FieldName"].Value<string>();
        var fieldValue = item["Value"].Value<string>();

        if (int.TryParse(fieldValue, out int fieldIntValue))
        {
            outputItem[fieldName] = fieldIntValue;
        }
        else
        {
            outputItem[fieldName] = fieldValue;
        }
    }

    var output = new JArray();
    output.Add(outputItem);

    var result = output.ToString();
    Console.WriteLine(result);
}

Console.WriteLine(result); writes following JSON:

[
  {
    "Id": 1234,
    "FieldName1": 2722,
    "FieldName2": "06/21/2022 13:03:11",
    "FieldName3": "XYZ"
  }
]

Answer 2

Basically, @Markus explained the concept of how to transform from the input to output.

This solution is worked with System.Linq and able to transform to multiple objects.

In case your data is:

[
  [ {...}, {...}, ... ], // Array 1
  [ ], // Array 2
  ...
]

1. Transform to JArray .
2. Iterate the (first-level) array item(s).
3. Iterate (second-level) array item(s) and add the item to become a dictionary.

using System.Linq;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

var result = JArray.Parse(json)
            .Select(x => 
            {
                Dictionary<string, dynamic> dict = new ();

                foreach (JObject jObj in x.ToObject<List<JObject>>())
                {
                    dict.Add(jObj["FieldName"].ToString(), Int32.TryParse(jObj["Value"].ToString(), out int @value) ? @value : jObj["Value"].ToString());    
                }

                return dict;
            })
            .ToList();

Sample .NET Fiddle