MVC: Is it considered bad form to give a DTO a reference to the data access layer?

Question

Is it considered bad form to give a DTO a reference to the data access layer?

Or should you always pass a DTO between the data access layer and the application layer?

EDIT: For example, imagine the following:

• I keep a product types list in my database.
• I'd like to render this list in a drop-down box in a partial view.
• This partial view is strongly-typed to a DTO.
• Question:
  • Should I retrieve my product types list first, and then pass it to the DTO via its constructor?
  • Or is it acceptable to pass a repository reference to the DTO, and then expect it to retrieve this list from the data access layer?

Answer 1

A DTO should never have a reference to the data access layer.

Rather a DTo is a simple transfer object that contains only data and is used to pass information between layers.