I have read several questions on here and it appears that the general consensus is that an interface is not required for every class in a project. I have read posts like this: Is it the best practice to extract an interface for every class?.
I want to know how this applies to the .NET framework classes. I believe that all of the classes I have looked at either inherit from an abstract class e.g. SQLConnection inherits from dbConnection or implement and interface e.g. the Component class implements the IComponent interface.
I have a copy of Reflector, which I downloaded two months ago and I am awaiting the license (paid the fee recently). When I start to step through the code (using Reflector); am I going to see code like this:
Public Class Foo Public Name As String Public Property NameProperty() Get Return Name End Get Set(value) Name = value End Set End Property Public Shared Sub Main() Dim f As Foo = New Foo f.NameProperty = "Ian" End Sub End Class rather than code like this:
Public Class Foo Implements IFoo Public Name As String Public Property NameProperty() Implements IFoo.NameProperty Get Return Name End Get Set(value) Name = value End Set End Property Public Shared Sub Main() Dim f As IFoo = New Foo f.NameProperty = "Ian" End Sub End Class Public Interface IFoo Property NameProperty() End Interface Notice that there is an Interface used in the second code fragment. I am still struggling to understand when it is suitable not to use interfaces. Some developers say never. I suppose some of it is subjective.
