The Model-View-Controller(MVC) Pattern with C#/WinForms

using System;
using System.Collections;
using WinFormMVC.Model;

namespace WinFormMVC.Controller
{
    public class UsersController
    {
        IUsersView _view;
        IList      _users;
        User       _selectedUser;

        public UsersController(IUsersView view, IList users)
        {
            _view = view;
            _users = users;
            view.SetController(this);
        }

        public IList Users
        {
           get { return ArrayList.ReadOnly(_users); }
        }

        private void updateViewDetailValues(User usr)
        {
           _view.FirstName   =  usr.FirstName;
           _view.LastName    =  usr.LastName;
           _view.ID          =  usr.ID;
           _view.Department  =  usr.Department;
           _view.Sex         =  usr.Sex;
        }

        private void updateUserWithViewValues(User usr)
        {
           usr.FirstName     =  _view.FirstName;
           usr.LastName      =  _view.LastName;
           usr.ID            =  _view.ID;
           usr.Department    =  _view.Department;
           usr.Sex           =  _view.Sex;
        }


        public void LoadView()
        {
            _view.ClearGrid();
            foreach (User usr in _users)
                _view.AddUserToGrid(usr);

            _view.SetSelectedUserInGrid((User)_users[0]);

        }

        public void SelectedUserChanged(string selectedUserId)
        {
            foreach (User usr in this._users)
            {
                if (usr.ID == selectedUserId)
                {
                    _selectedUser = usr;
                    updateViewDetailValues(usr);
                    _view.SetSelectedUserInGrid(usr);
                    this._view.CanModifyID = false;
                    break;
                }
            }
        }


        public void AddNewUser()
        {
            _selectedUser = new User(""/*firstname*/, 
                                     "" /*lastname*/, 
                                     ""  /*id*/, 
                                     "" /*department*/,
                                     User.SexOfPerson.Male /*sex*/);
                                     
            this.updateViewDetailValues(_selectedUser);
            this._view.CanModifyID = true;
        }

        public void RemoveUser()
        {
            string id = this._view.GetIdOfSelectedUserInGrid();
            User userToRemove = null;

            if (id != "")
            {
                foreach (User usr in this._users)
                {
                    if (usr.ID == id)
                    {
                        userToRemove = usr;
                        break;
                    }
                }

                if (userToRemove != null)
                {
                    int newSelectedIndex = this._users.IndexOf(userToRemove);
                    this._users.Remove(userToRemove);
                    this._view.RemoveUserFromGrid(userToRemove);

                    if (newSelectedIndex > -1 && newSelectedIndex < _users.Count)
                    {
                        this._view.SetSelectedUserInGrid((User)_users[newSelectedIndex]);
                    }
                }
            }
        }

        public void Save()
        {
            updateUserWithViewValues(_selectedUser);
            if (!this._users.Contains(_selectedUser))
            {
                // Add new user
                this._users.Add(_selectedUser);
                this._view.AddUserToGrid(_selectedUser);
            }
            else
            {
                // Update existing
                this._view.UpdateGridWithChangedUser(_selectedUser);
            }
            _view.SetSelectedUserInGrid(_selectedUser);
            this._view.CanModifyID = false;

        }

    }
}