c# – WPF MVVM Light单元测试ViewModels

我曾经做过的(“正常”WPF)正在创建一个业务层和数据层(通常包含由一个服务或实体框架创建的实体)的视图.

现在经过一段折磨,我创建了一个MVVM Light的标准模板,并做到这一点：

定位：

public class ViewModelLocator
{
    static ViewModelLocator()
    {
        ServiceLocator.SetLocatorProvider(() => SimpleIoc.Default);

        if (ViewModelBase.IsInDesignModeStatic)
        {
            SimpleIoc.Default.Register<IUserService,DesignUserService>();
        }
        else
        {
            SimpleIoc.Default.Register<IUserService,IUserService>();
        }

        SimpleIoc.Default.Register<LoginViewModel>();
    }

    public LoginViewModel Login
    {
        get
        {
            return ServiceLocator.Current.GetInstance<LoginViewModel>();
        }
    }
}

登录ViewModel：

public class LoginViewModel : ViewModelBase
{
    private readonly IUserService _userService;

    public RelayCommand<Object> LoginCommand
    {
        get
        {
            return new RelayCommand<Object>(Login);
        }
    }

    private string _userName;
    public String UserName
    {
        get { return _userName; }
        set
        {
            if (value == _userName)
                return;

            _userName = value;
            RaisePropertyChanged("UserName");
        }
    }

    /// <summary>
    /// Initializes a new instance of the LoginViewModel class.
    /// </summary>
    public LoginViewModel(IUserService userService)
    {
        _userService = userService;

        _closing = true;
    }

    private void Login(Object passwordBoxObject)
    {
        PasswordBox passwordBox = passwordBoxObject as PasswordBox;
        if (passwordBox == null)
            throw new Exception("PasswordBox is null");

        _userService.Login(UserName,passwordBox.SecurePassword,result =>
        {
            if (!result)
            {
                MessageBox.Show("Wrong username or password");
            }
        });
    }
}

绑定和命令工作正常,所以没有问题.商业模型课设计考试时间：

public class DesignUserService : IUserService
{
    private readonly User _testUser;
    private readonly IList<User> _users;

    public void Login(String userName,SecureString password,Action<Boolean> callback)
    {
        var user = _users.FirstOrDefault(u => u.UserName.ToLower() == userName.ToLower());

        if (user == null)
        {
            callback(false);
            return;
        }

        String rawPassword = Security.ComputeHashString(password,user.Salt);
        if (rawPassword != user.Password)
        {
            callback(false);
            return;
        }

        callback(true);
    }

    public DesignUserService()
    {
        _testUser = new User
        {
            UserName = "testuser",Password = "123123",Salt = "123123"
        };

        _users = new List<User>
        {
            _testUser
        };
    }
}

UserData是一个静态类,它调用数据库(Entity Framework).

现在我有我的考试：

[TestClass]
public class Login
{
    [TestMethod]
    public void IncorrectUsernameCorrectPassword()
    {
        IUserService userService = new DesignUserService();

        PasswordBox passwordBox = new PasswordBox
        {
            Password = "password"
        };
        userService.Login("nonexistingusername",b => Assert.AreEqual(b,false));
    }
}

现在我的测试不是在ViewModel本身,而是直接到业务层.

基本上我有两个问题：

我在正确的道路上,还是我的模式实现有根本的缺陷？
>如何测试我的ViewModel？