DataTable To Json

using System.Collections.Generic;
using System.Data;
using System.Text;
using System.IO;
using Newtonsoft.Json;

namespace MatchGroupSystem.Common
{
    public class JsonMethods
    {
        public static string datatableToJSON(DataTable dt)
        {
            StringBuilder jsonStringBuilder = new StringBuilder();
            StringWriter jsonStringWriter = new StringWriter(jsonStringBuilder);

            JsonWriter jsonWriter = new JsonTextWriter(jsonStringWriter);

            if (dt != null && dt.Rows.Count > 0)
            {
                jsonWriter.Formatting = Newtonsoft.Json.Formatting.None;

                jsonWriter.WriteStartArray();
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    jsonWriter.WriteStartObject();
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        jsonWriter.WritePropertyName(dt.Columns[j].ColumnName.ToString());
                        jsonWriter.WriteValue(dt.Rows[i][j].ToString());
                    }
                    jsonWriter.WriteEndObject();
                }
                jsonWriter.WriteEndArray();

                return jsonStringBuilder.ToString();
            }
            else
            {
                return null;
            }
        }

    }
}