using System;
using Newtonsoft.Json;
using System.Collections.Generic;

public class Employee
{
    public Employee(string lastName, string firstName) {
        FirstName = firstName;
        LastName = lastName;
    }
    public string FirstName { get; set; }
    public string LastName { get; set; }
}


var employees = new List<Employee>();

employees.Add(new Employee("John", "Doe"));
employees.Add(new Employee("Anna", "Smith"));
employees.Add(new Employee("Peter", "Jones"));

var json = JsonConvert.SerializeObject(employees);

Console.WriteLine($"json: {json}");

employees = JsonConvert.DeserializeObject<List<Employee>>(json);

employees.ForEach(x => Console.WriteLine($"First: {x.FirstName}  Last: {x.LastName}"));