Mocking DbEntityEntry.CurrentValues.SetValues() in EF4 CTP5 Code First

Question

I am trying to use the DbEntityEntry.CurrentValues.SetValues() method to facilitate updating an existing entity with values from a non-entity DTO (see: http://blogs.msdn.com/b/adonet/archive/2011/01/30/using-dbcontext-in-ef-feature-ctp5-part-5-working-with-property-values.aspx)

I'm having trouble removing the dependency on DbEntityEntry though (for mocking, testing). Here is an example of what I would like to do:

var entity = dbSet.Find(dto.Id);
var entry = context.Entry(entity);
entry.CurrentValues.SetValues(dto);
context.SaveChanges();

I've also considered:

EntityType entity = new EntityType() { Id = dto.Id };
context.Attach(entity);
var entry = context.Entry(entity);
entry.CurrentValues.SetValues(entity);
context.SaveChanges();

From what I've been able to find both seem reasonable when working with an actual DbContext, but when I abstract the context to an IMyContext I lose the capability to get a DbEntityEntry for an entity, thus losing the SetValues option.

Is there any way to work around this issue, or do I need to bite the bullet and manually set modified properties on the entity from the DTO (potentially a lot of boilerplate for entities with many properties)?

(I'm fairly new to EF and this is my first StackOverflow question, so please be gentle)

score 0 · Answer 1 · answered Nov 28 '11 at 20:48

If you have never used it before, this would be a great use for AutoMapper (also available via NuGet). I am unaware of how to solve your IMyContext issue and would also resort to mapping the properties. But instead of doing so manually, I would allow AutoMapper to do the heavy lifting.

Mocking DbEntityEntry.CurrentValues.SetValues() in EF4 CTP5 Code First

1 Answers1