Entity Framework 4 Unit of Work / Repository WITHOUT .Query() Lambda

Question

We've seen some very useful methods of implementing EF4 Repository and Unit of Work pattern (Reference 1, Reference 2)

All the examples I see use methods requiring the use of LINQ Expression Syntax, e.g.:

IEnumerable<T> Query(Expression<Func<T, bool>> filter) 

var employees = employeeRepository.Query(emp => emp.Username == userName);

But I want to use LINQ Query Expression syntax, e.g.:

from emp in context.Employees select emp where emp.Username == userName;

Is there a way to enjoy the benefits of a repository and UoW whilst being able to use LINQ Query Expression syntax in my repository methods?

Richard

score 2 · Accepted Answer · edited May 23 '17 at 10:08

2

Yes but you must expose IQueryable<T>:

IQueryable<T> Query();

After that you can use code like:

var query = from emp in EmployeeRepository.Query() 
            where emp.Username == userName
            select emp;

The difference between approaches was discussed yesterday. Also whole concept of repository and unit of work was discussed many times - including why to use them and what problems you can expect.

edited May 23 '17 at 10:08

Community

answered Jun 21 '11 at 06:41

Ladislav Mrnka

+1 That's the way I do it too. It still enables lambda expressions such as employeeRepository.Query().Where(emp => emp.UserName == userName); – Danny Varod Jun 21 '11 at 08:53
That looks good. I know the repository discussion has been done to death. Funny 2 discussions on this topic hit around the same time :) I think the fact there are so many discussions around these topics serves to highlight some pretty serious weaknesses in EF4. – Richard Jun 21 '11 at 22:56

1 Answers1