Entity Value Comparison

[joewmaki]

I need to reference the original values of an entity before doing a SaveChanges(). Is the value in the store available and what is the syntax to access it?

Example: I have an Employee entity and change the Hours of the employee. How can I determine, before I implement the SaveChanges() that Hours has been modified?

[joewmaki]

Figured out a solution:

Sub CheckModifiedValues(ByVal Context As ObjectContext)
        Try
            'Get all objects modified
            Dim Changes As IEnumerable(Of ObjectStateEntry) = Context.ObjectStateManager.GetObjectStateEntries(EntityState.Modified)
            If Changes.Count > 0 Then
                'Loop through changed objects
                For Each Obj In Changes
                    'get the properties modified for the object
                    Dim ModifiedProperties As IEnumerable(Of String) = Obj.GetModifiedProperties
                    If ModifiedProperties.Count > 0 Then
                        For Each prop As String In ModifiedProperties
                            'these will error if you pass through a property that was not modified - thus the GetModifiedProperties
                            Dim strOrg As String = Obj.OriginalValues(prop).ToString
                            Dim strMod As String = Obj.CurrentValues(prop).ToString
                            MessageBox.Show("Current " & prop & ": " & strMod & " Original " & prop & ": " & strOrg)
                        Next
                    End If
                Next
            End If
        Catch ex As Exception
            MessageBox.Show(ex.Message)
        End Try
    End Sub