带有存储库的Asp.net MVC的替代方案

Question

There seem to be many guides pushing the use of Entity Framework with the Repository and Unit of Work patterns when developing ASP.Net MVC projects.

A quick Google yields countless discussion on the Pro and Cons of this approach and while those who oppose the use of these patterns with EF are vocal I have yet to see anyone detail a good alternative.

Short of directly accessing EF in Controller classes what's another approach to the Data Access layer?

Answer 1

I used repositories a lot in the past; I thought they were the best thing since sliced bread.

However, over time and with gaining experience, I stopped using the repository pattern. My repo classes inevitably ended up being clogged with numerous methods, many of which almost mimicked stored procs e..g

customerRepo.GetCustomerWithFooBar();

sp_GetCustomerWithFooBar

I didn't deliberately look for an alternative per se, but I ended up using one of two ways.

1. Entity Framework Context I simply coded against the context object itself; running LINQ queries as well as the usual SaveChanges() type of stuff.

That looked messy, but it reduced the level of abstraction. But, as my project and code got bigger, this method wasn't that that maintainable. SO I tried...

1. CQS (Command Query Separation) The idea is to have classes the do commands and other classes that perform query's. eg

   public class SaveCustomerCommand(){}

   public class ListCustomerQuery(){}

That way, I was able to nicely abstract my Entity Framework code into two categories - those classes that changed the data, and those which simply read it. Unfortunately, I never finished the code where I experimented with this approach, but you could consider writing a CommandDispatcher class that takes in commands/query's, new's up UnitOfWork object (however you implemented that) and control the command.Execute() and query.Execute().

There are articles out there which could help you get up and running with method 2.

http://alertcoding.wordpress.com/2013/03/17/command-and-query-based-entity-framework-architecture/