Thursday, June 28, 2012

No ELMAH, forget about it!

If you haven't heard of ELMAH you need to check out the following links pronto!

ELMAH - Home
Scott Hanselman on ELMAH

I highly recommend using ELMAH whenever you can when developing custom applications. There are very few things that you can "bolt-on" to your application that will provide so much functionality with so little effort.

But what happens when you can't use ELMAH? If for some reason you can't use ELMAH in your application (like, for say... you work with an old school architect who just doesn't get it, and doesn't want to try to get it) then what do you do? What you do is forget about it, and write your own!

Wednesday, June 27, 2012

Using Pete Montgomery’s Universal Predicate Builder with a generic repository

I gave a presentation the other day that included a generic repository class that I created and use in many of my Entity Framework projects. I like the implementation because it is flexible and easy to extend. I've created a blog post about the RepositoryBase class here:

A Generic Repository for the Entity Framework

After the presentation I was asked how I utilized the repository's Select methods. In this case, the Select Method is overridden a few times to match the select pattern used by ASP.Net ObjectDataSources. Essentially, I can create a repository class that will map 1 to 1 to an ObjectDataSource to enable paging and sorting.

Wednesday, June 13, 2012

A Generic Repository for the Entity Framework

Note: In this post I am going to be demonstrating techniques that depend on the Entity Framework 4.1 or higher.

Recently I’ve been using a simple Repository oriented architecture for my Entity Framework projects. Coupled with the new DbContext class and the entity code generation items added in the Entity Framework 4.1 release you can quickly scaffold up a data layer and business layer for your application.

To start, let’s define an interface for our repository:

public interface IRepository : IDisposable
    void Insert<E>(E entity) where E : class;

    void Update<E>(E entity) where E : class;

    void Delete<E>(E entity) where E : class;

    IQueryable<E> Select<E>() where E : class;

    E Select<E>(object key) where E : class;

    int SaveChanges();

    int SaveChanges(bool validateEntities);