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c# - Custom JSON string output using Newtonsoft

I'm trying to serialize C# DataTable using Newtonsoft JsonConverter

Code :

JsonConvert.SerializeObject(dt); //dt is DataTable

Result I got is :

[
  {
    "Name": "Tiger Nixon",
    "Position": "System Architect",
    "Address": "Edinburgh",
    "No": "5421"
  },
  {
    "Name": "Garrett Winters",
    "Position": "Accountant",
    "Address": "Tokyo",
    "No": "8422"
  }
]

Result I want is :

{
  "data": [
    [
      "Tiger Nixon",
      "System Architect",
      "Edinburgh",
      "5421"
    ],
    [
      "Garrett Winters",
      "Accountant",
      "Tokyo",
      "8422"
    ]
  ]
}

Is it possible to custom the output using Newtonsoft? I tried writing my own code to serialize the DataTable by using foreach on the DataTable but the performance is night and day compared to Newtonsoft.

Any help will be appreciated

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You could do it with the following JsonConverter:

public class DataTableTo2dArrayConverter : JsonConverter
{
    public override bool CanConvert(Type objectType)
    {
        return typeof(DataTable).IsAssignableFrom(objectType);
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        throw new NotImplementedException();
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        var table = (DataTable)value;
        var array2d = table.AsEnumerable().Select(row => table.Columns.Cast<DataColumn>().Select(col => row[col]));
        serializer.Serialize(writer, new { data = array2d });
    }
}

And then use it like:

        var settings = new JsonSerializerSettings();
        settings.Converters.Add(new DataTableTo2dArrayConverter());
        var json = JsonConvert.SerializeObject(dt, Formatting.Indented, settings);

Note that my use of System.Data.DataTableExtensions.AsEnumerable() requires a reference to System.Data.DataSetExtensions.dll.


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