Entity Framework: WinForms databinding in EF4.1 – DBSet

Solved

Dim context As New SOPEntities
System.Data.Entity.DbExtensions.Load(context.Employees.Where(Function(f) f.Current = True).OrderBy(Function(g) g.FullName))
EmployeeBindingSource.DataSource = context.Employees.Local
ListBox1.DataSource = System.Data.Entity.DbExtensions.Tobindinglist(context.Employees.Local)
ListBox1.DisplayMember = “FullName”

Problem

‘local’ is not a member of ‘System.Data.Objects.ObjectSet(Of <entityname>)’

See http://wp.me/p17IS4-ih

Solved

Open the <Name>Model.edmx > Right click > Add code generation item…

Choose ADO.Net DbContext Generator. This has affect of changing the .edmx file Code Generation Strategy to “None” and creates a text template model and .Local now works.

Discussion

Uses EF4.1 EntityFramework.dll
Database first, then add code generation item to get T4 simpler classes and DBSet inherits DBContext
Initially could not work out how to get the Load method. See above for solution.
There is no MSDN VB.Net sample yet. The C# is more like context.Employees.Local.ToBindingList. So it took me a while to work out the syntax above.

Unsolved:
Also the FullName is now a computed column in the database. Was unable to work out how to do this in EF. It may come in the future as a “Model Defined Function”. Do not think this is a Scalar or Complex Type which is something else.
Unsolved:
For BindingSource to support complex filter it needs to support IBindingListView. Typically EF does not.

Links

Binding Objects to Controls
http://msdn.microsoft.com/en-us/library/gg197521(v=VS.103).aspx

Following is in C#
http://msdn.microsoft.com/en-us/library/gg197523(v=VS.103).aspx