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CSharp · Console

/Program.cs

using System;
using CsvHelper;
using Newtonsoft.Json;
using System.Globalization;
using System.IO;

public class Program
{
	public static void Main()
	{
		var txtInput = "a,b,c\n1,2,3\n4,5,6";
		string output;
		using (var reader = new StringReader(txtInput))
			using (var csvReader = new CsvReader(reader, CultureInfo.InvariantCulture))
		{
			var records = csvReader.GetRecords<dynamic>();
			output = JsonConvert.SerializeObject(records, Formatting.Indented);
		}

		Console.WriteLine(output);
	}
}