Interfaces and workarounds for differences in C# and VB

[balabaster]

I've got a hierarchy of interfaces that I need passed into a method to return a value given a value path. For instance:

Class.Property.SubProperty.Value

I'm using reflection to iterate through the path grabbing the sub-properties down to the "leaf" property at which point the value is returned. The basic concept is this:

Function GetValue(ByVal FreightBill As IFreightBill, ByVal ValuePath As String) As Double
 
  Dim AssemblyName As String = Reflection.Assembly.GetExecutingAssembly().GetName.Name
 
  Dim PathNodes As List(Of String) = ValuePath.Split(".").ToList
  If PathNodes(0) <> AssemblyName Then PathNodes.Insert(0, AssemblyName)
 
  Dim CrntInstance As Object = FreightBill
  For i As Integer = 2 To PathNodes.Count - 1
    Dim CrntType As Type = CrntInstance.GetType()
    Dim CrntProperty As String = PathNodes(i)
    Dim dynProperty As Reflection.PropertyInfo = CrntType.GetProperty(CrntProperty)
    Dim CrntValue = dynProperty.GetValue(CrntInstance, _
                                   System.Reflection.BindingFlags.GetProperty, _
                                   Nothing, _
                                   Nothing, _
                                   Nothing)
    CrntInstance = CrntValue
 
  Next
  Return CrntInstance
 
End Function

Now...even if I replace some of my properties from static classes to interfaces, in C# this will still work as when you implement an interface in C# it must have the same name as the interface, so everything works as you would expect. But if you implement an interface in VB, you can change the name of a property because each property uses the Implements keyword to implement the correct property of the interface. For example:

Public Property MyIncorrectlyNamedProperty() As String Implements IMyInterface.ActualPropertyName

Whereas in C#, you must use the correct name...

So my question I guess is in order to prevent possible problems with VB programmers calling instance properties by incorrect names, what can I do about this? Other than rapping them on the knuckles with a ruler and telling them not to do that...

[balabaster]

I wondered if creating a dynamic instance of an object that implements the interface that the property represents would help...

So if I am handling a property with some declaration to:

Interface IPropertyInterface
  Property MyValue() As String
End Interface
 
Interface IInstanceInterface
  Property MyProperty() As IPropertyInterface
End Interface
 
Public Class MyProperty
  Implements IMyProperty
 
  Private _MyValue As String
  Public Property MyValue() As String
    Get
      Return _MyValue
    End Get
    Set (ByVal value As String)
      _MyValue = value
    End Set
  End Property
End Class
 
Public Class MyInstance
  Implements IInstanceInterface
 
  Private _MyProperty As IPropertyInterface
  Public Property MyProperty() As IPropertyInterface Implements IInstanceInterface.MyProperty
    Get
      Return _MyProperty
    End Get
    Set (ByVal value As IPropertyInterface)
      _MyProperty = value
    End Set
  End Property
End Class

So I can use the following:

Dim oInst As New MyInstance
Dim oProp As New MyProperty
oProp.MyValue = "Hello World"
oInst.MyProperty = oProp
 
Dim OutStr As String = GetValue(oInst, "ObjectInstance.MyProperty.MyValue")
Console.WriteLine(OutStr)

So my GetValue method (previously posted) would iterate over the instance without any issues...but if the class that implements IInstanceInterface had it's MyProperty property changed to MyIncorrectlyNamed property... I'm wondering if I could grab the property rather than by name, but by the interface it implements...

[balabaster]

Actually, I think I might just like the "rap them on the knuckles" approach...

[Plater]

Actually, I think I might just like the "rap them on the knuckles" approach...

I was going to suggest you use a mallet or something larger then a ruler.

[balabaster]

I was going to suggest you use a mallet or something larger then a ruler.

That's not in the stationary budget :oP