Using TimeServices with Dependency Injection

TimeServices was created with Dependency Injection in mind, whether you use Poor Man's Dependency Injection or you use a Dependency Injection Container.

When you create new classes which access to time, then make sure you you depend on a IClock. This way you can always switch implementation.

A example using constructor injection:

public class UserService
{
    private readonly IClock _clock;

    public UserService(IClock clock)
    {
        _clock = clock;
    }

    public User CreateNewUser(string name)
    {
        return new User
                    {
                        Name = name,
                        CreationDate = _clock.Now
                    };
    }
}

Another example, but this time using property injection with the SystemClock as default (so it will still work, if nothing gets injected):

public class UserService
{
    private IClock _clock = SystemClock.Instance;

    public IClock Clock
    {
        get { return _clock; }
        set { _clock = value; }
    }

    public User CreateNewUser(string name)
    {
        return new User
                    {
                        Name = name,
                        CreationDate = Clock.Now
                    };
    }
}