.NET Enums

I like Enum. I love how you can define an Enum like this:

    Enum ColorType 
        Red 
        Green 
        Blue 
    End Enum

Then use it as a parameter type like this:

    Public Sub ProcessColor(color As ColorType)

    End Sub

And when you go to use it in a method you get intellisense like this:

List of Enums Blue, Green, Red.










Every so often I come across a data model that uses strings to signify types. Like an 'R' for Red and 'G' for Green and a 'B' for Blue. I would love to use my good friend Enum and go:

    Enum ColorType 
        Red = "R" 
        Green = "G" 
        Blue = "B" 
    End Enum

But unfortunately this is not possible.  If you are like me and wish you could do this please go here: http://visualstudio.uservoice.com/forums/121579-visual-studio/suggestions/2161129-string-enum-for-both-c-and-vb and Vote now.

Until we get enough votes to get this implemented my current favorite alternative is to define a class like this:

    Class ColorType 

        Private Sub New(aColorType As String) 
            Value = aColorType 
        End Sub 

        Public Shared ReadOnly Property Red() As ColorType
            Get 
                Return New ColorType("R") 
            End Get 
        End Property 

        Public Shared ReadOnly Property Green() As ColorType
            Get 
                Return New ColorType("G") 
            End Get 
        End Property 

        Public Property Value() As String
        Public Shared ReadOnly Property Blue As ColorType
            Get 
                Return New ColorType("B") 
            End Get 
        End Property 

        Public Shared Operator <>(object1 As ColorType, object2 As ColorType) As Boolean
            Return Not object1.Value.Equals(object2.Value)
        End Operator 

        Public Shared Operator =(object1 As ColorType, object2 As ColorType) As Boolean
            Return object1.Value.Equals(object2.Value) 
        End Operator 

        Public Shared Widening Operator CType(aColorType As ColorType) As String
            Return aColorType.Value 
        End Operator 

    End Class 

Unless there is a lot of logic around the different types then it might be good for a Replace Type Code refactoring like: http://www.refactoring.com/catalog/replaceTypeCodeWithSubclasses.html

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