ASP.Net MVC 3 - unitOfWork.Commit() not saving any

I created a web application using ASP.Net MVC 3 and EF 4.1, and I am using the UnitOfWork pattern, but nothing is getting committed to the database. All this is quite new to me, and I don't know where to start to resolve this issue.

I based myself on this post to create my web application:

http://weblogs.asp.net/shijuvarghese/archive/2011/01/06/developing-web-apps-using-asp-net-mvc-3-razor-and-ef-code-first-part-1.aspx

The final code, which can be obtained here also has a service layer and the UnitOfWOrk is being injected into the services.

Instead of using the custom injector based on Unity 2 as they are in that project, I am using Unity.Mvc3.

Here is my IUnitOfWork class:

public interface IUnitOfWork
{
    void Commit();
}

And here is my UnitOfWork class:

public class UnitOfWork : IUnitOfWork
{
    private readonly IDatabaseFactory databaseFactory;
    private MyProjectContext dataContext;

    public UnitOfWork(IDatabaseFactory databaseFactory)
    {
        this.databaseFactory = databaseFactory;
    }

    protected MyProjectContext DataContext
    {
        get { return dataContext ?? (dataContext = databaseFactory.Get()); }
    }

    public void Commit()
    {
        DataContext.Commit();
    }
}

And here is how one of my service class look like:

public class RegionService : IRegionService
{
    private readonly IRegionRepository regionRepository;
    private readonly IUnitOfWork unitOfWork;
    public RegionService(IRegionRepository regionRepository, IUnitOfWork unitOfWork)
    {
        this.regionRepository = regionRepository;
        this.unitOfWork = unitOfWork;
    }  
    ...
}

At start-up, my UnitOfWork component is being registered like this:

container.RegisterType<IUnitOfWork, UnitOfWork>();

Now, no matter whether I try to insert, update or delete, no request is being sent to the database. What am my missing here?

UPDATE:

Here is the content of DataContext.Commit():

public class MyProjectContext : DbContext
{
     public DbSet<Region> Regions { get; set; }

    public virtual void Commit()
    {
        base.SaveChanges();
    }
}

And here is databaseFactory.Get():

public interface IDatabaseFactory : IDisposable
{
    MyProjectContext Get();
}

UPDATE #2:

Using the debugger, I am noticing that my Region service and controller constructors are getting called once when performing only a select, but they are called twice when performing an update. Is this normal?

回答1:

Ok, I found the culprit. It has to do with how I was registering my database factory.

Instead of

container.RegisterType<IDatabaseFactory, DatabaseFactory>();

I needed

container.RegisterType<IDatabaseFactory, DatabaseFactory>(new HierarchicalLifetimeManager());

I found the information on this web site:

http://www.devtrends.co.uk/blog/introducing-the-unity.mvc3-nuget-package-to-reconcile-mvc3-unity-and-idisposable

回答2:

That's an awfully complex implementation of Unit of Work. I actually prefer this one:

http://azurecoding.net/blogs/brownie/archive/2010/09/22/irepository-lt-t-gt-and-iunitofwork.aspx

Much simpler, and much more flexible. Although you do have to work out a few things for yourself.

回答3:

May just be a typo but in UnitOfWork your private MyProjectContext is called dataContext (lowercase d)

But in your commit method your calling DataContext.Commit. Any chance that's actually calling a static method that you didn't intend to call? More likely a typo but thought I'd point it out.

+1 for an overly complex implementation of UnitOfWork.