
Visual Studio LightSwitch allows you to create Business Type extensions. A
Business Type “enables you to present data in a way that is most appropriate for your application without changing the data type in which the data is stored
in the underlying database”. In this article we will create a
Business Type for a Customer Code. The underlying type will be a
String, but the Business Type will be a custom type that requires the first character to not be a number and for it to be at least 10 characters long. It will also have its own custom control for display and editing.
See the full article here:
http://lightswitchhelpwebsite.com/Blog/tabid/61/EntryId/99/Creating-a-LightSwitch-Business-Type-Extension.aspx
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