Callbacks with Entity Framework 4.3 Code First?
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Is the concept of callbacks available in Entity Framework when taking a Code First approach?  

I am looking for a way to update model properties when an instance is created, updated, or deleted.  Examples:

1. For an Order object (which btw are represented a simple POCO class), depending on the total amount I want to set the Status property to either "READY" or "TO_REVIEW" on create and update.

2. Any model that has a CreatedAt property ... I want to have that set = DateTime.Now on creation automatically.

3. Any model that has an UpdatedAt property ... I want to have that set = DateTime.Now on update automatically.

Coming from Rails development, you have a number of hooks you can utilize at different periods in the lifecycle of your model objects.  I'm hoping something similar is available in the .NET world when going EF and Code-First.

Thanks