Make Base Interface For Generic Classes?

May 25, 2010

I'm trying to create a base interface for a class of mine that uses generics. However, I cannot figure out how to declare a property of the interface when its type won't be defined until the class is initialized.

To clarify, consider List(of T), which according to msdn, implements IList (among other things). Note that IList is not the same as its generic counterpart IList(Of T). So that mean any List(of T) can be converted to IList, which simply returns an object for its items. That's what I want to do with MyClass(of T), be able to cast it as IMyClass regardless of what T is.

But when I try such as:

Interface IMyClass
Prop A as Object
Class MyClass(of T) Implements IMyClass
Prop A as T Implements IMyClass.A

I get a signature error for the last line, even though object is broader than T. What am I doing wrong, or how exactly did Microsoft manage to make List(of T) implement IList?

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Consider:

Public MustInherit Class Column
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Get
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[code]....

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Public Overrides Function ParseValue(sValue As String) As Boolean'
cannot override 'Public Overridable Function ParseValue(sValue As String) As Object'
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<DataContract()> _
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[Code]...

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[Code]....

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[Code]...

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[Code]....

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This is the code I'm trying to develop:

Public Structure Statistic(Of t)
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[Code].....

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[Code]...

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[code]....

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[Code]...

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[Code]...

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[Code]....

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[code].....

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I have an interface called IRow (and a class that implements it as a Datarow).

A second interface is ICanGetByRow, which looks like this:

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My interface was enhanced by the following function

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Dim foo As New T
foo.GetByRow(Me)
Return foo
End Function

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[Code] .....

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