private static Message CreateResponseMessage()
        {
            HttpResponseMessage response = new HttpResponseMessage(HttpStatusCode.OK);
            Employee employee = new Employee("001", "Zhang San", "123456", "*****@*****.**");
            response.Content = new ObjectContent<Employee>(employee, new JsonMediaTypeFormatter());

            string httpMessageTypeName = "System.Web.Http.SelfHost.Channels.HttpMessage, System.Web.Http.SelfHost";
            Type httpMessageType = Type.GetType(httpMessageTypeName);
            return (Message)Activator.CreateInstance(httpMessageType, new object[] { response });
        }
 public void Update(Employee employee, int Id)
 {
     Employee emp = employees.Where(x => x.EmployeeId.Equals(Id)).FirstOrDefault();
     emp.EmployeeName = employee.EmployeeName;
     emp.ManagerId = employee.ManagerId;
 }
 public void Add(Employee employee)
 {
     employees.Add(employee);
 }