append json

json.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
using Jil;

namespace ConsoleApplication8
{
  class Program
  {
    static void Main(string[] args)
    {
      var movies = Load();
      var highrated = movies.Where(x => x.Rating > 8).ToList();

    }

    static void Save(IEnumerable<Movie> items)
    {
      using (var fs = File.Open("store.json", FileMode.Append))
      using (var writer = new StreamWriter(fs))
      {
        foreach (var item in items)
        {
          var json = JSON.Serialize<Movie>(item);
          writer.WriteLine(json);
        }
      }
    }

    static IEnumerable<Movie> Load()
    {
      var lines = File.ReadAllLines("store.json");
      var movies = lines.Select(x => JSON.Deserialize<Movie>(x));

      return movies;
    }
  }

  public class Movie
  {
    public int Id { get; set; }
    public string Name { get; set; }
    public string Year { get; set; }
    public float Rating { get; set; }
    public int Votes { get; set; }
    public List<int> Directors { get; set; }
    public List<int> Writers { get; set; }
    public List<int> Actors { get; set; }

  }

}