Creating entity objects for insertion in Entity Framework 6

Question

Through examples in the past, I have learned to use DbSet<TEntity>.Create() to create entity objects for insertion. However, I have found just using the default constructor with an object initializer seems to work just as well.

My main question is, do we ever still need to use DbSet<TEntity>.Create(), and why?

Bonus question: What, if any, is the functional difference between these two code examples?

"By the book":

    Dim db As New EFDAL.WidgetDbEntities()
    Dim dbWidgetBatch2 As EFDAL.WidgetBatch = db.WidgetBatches.Create()
    dbWidgetBatch2.CreationTimestamp = Now
    dbWidgetBatch2.CreatedByUsername = userName
    db.WidgetBatches.Add(dbWidgetBatch2)
    db.SaveChanges()

"Works just as well?":

    Dim db As New EFDAL.WidgetDbEntities()
    Dim dbWidgetBatch As New EFDAL.WidgetBatch With {
        .CreationTimestamp = Now,
        .CreatedByUsername = userName
    }
    db.WidgetBatches.Add(dbWidgetBatch)
    db.SaveChanges()

Duplicate of http://stackoverflow.com/questions/7311949/ramifications-of-dbset-create-versus-new-entity — Wiktor Zychla, May 12 '14 at 18:04

score 0 · Accepted Answer · answered May 13 '14 at 13:27

After reviewing the duplicate candidate, I see the main subject matter of this question has already been covered. However I feel it's worthwhile to summarize how the concepts apply to my question.

If I understand correctly, the short answer is that DbSet.Create() creates a "proxied" object which enables, among other things, lazy loading of navigation properties.

In the examples I posted, no navigation properties were used so both examples do in fact work equivalently, and for most inserts I suspect most people will not need a proxied object.

Links:

http://msdn.microsoft.com/en-us/data/jj592886.aspx - Helped me understand proxying better
http://msdn.microsoft.com/en-us/library/gg679504(v=vs.113).aspx - Reference on Dbset.Create()

An alternative to using `DbSet.Create()` is using `Entry(model).Reference(o => MyRef).Load()` after `model` has been added to the DB context. For example: if `model.MyRefId` has a value then the corresponding entity of `model.MyRef` will be loaded. I find this useful when working with ASP.NET MVC applications and the out-of-the-box model binder. — Jeremy Cook, May 13 '14 at 13:52

Creating entity objects for insertion in Entity Framework 6

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