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CSharp · Console

/Program.cs

using System;
using System.Diagnostics;
using System.Text;
using System.Linq;
					
public class Program
{
	public static void Main()
	{
		var list = new string[3][] {
			new string[3] { "a","b","c" },
			new string[3] {"1","2","3" },
			new string[3] {"4","5","6"}
		};
		
		var json = toJson(list);
		Console.WriteLine(json);
	}
	
	public static string toJson(string[][] csvArray) {
		var sb = new StringBuilder("{\n\"elements\": [\n");
		var headers = new string[csvArray[0].Length];
		
		for(int i = 0; i < csvArray[0].Length; i++)
		{
			headers[i] = csvArray[0][i];
		}
		
		for(int i = 1; i < csvArray.Length; i++)
		{
			sb.AppendLine("{");
			for(int j = 0; j < csvArray[i].Length; j++)
			{
				sb.AppendLine("\"" + headers.ElementAtOrDefault(j) + "\": \"" + csvArray[i][j] + "\",");
			}
			sb.Remove(sb.Length-3, 3); // remove last ",/n" to make json valid
			sb.AppendLine("\n},");
		}
		sb.Remove(sb.Length-3, 3); // remove last ",/n" to make json valid
		sb.AppendLine("\n]\n}");
		
		return sb.ToString();
	}
}