Option Strict On issues where generic type isn't known until runtime

Question

I have the following code that has worked fine for months, but I forgot to create this class with Option Strict On so now I am going back to clean up my code correctly, however I haven't been able to figure out a way around the following issue.

I have a local variable declared like this:

Private _manageComplexProperties

Now with option strict, this isn't allowed due to no As clause which I understand, however the reason that it is like this is because the instance of the class that will be assigned to it takes a type parameter which isn't known until run time. This is solved by the following code:

Private _type As Type
*SNIP OTHER IRRELEVANT VARIABLES*

Public Sub Show()

    Dim requiredType As Type = _
        GetType(ManageComplexProperties(Of )).MakeGenericType(_type)

    _manageComplexProperties = Activator.CreateInstance(requiredType, _
         New Object() {_value, _valueIsList, _parentObject, _unitOfWork})

    _result = _manageComplexProperties.ShowDialog(_parentForm)
    If _result = DialogResult.OK Then
        _resultValue = _manageComplexProperties.GetResult()
    End If

End Sub

Again option strict throws a few errors due to late binding, but they should be cleared up with a cast once I can successfully declare the _manageComplexProperties variable correctly, but I can't seem to get a solution that works due to the type parameter not known until run time. Any help would be appreciated.

Answer 1

Declare your variable as Object

Private _manageComplexProperties as Object

And then you will have to persist with reflection, e.g. to call ShowDialog method:

Dim method As System.Reflection.MethodInfo = _type.GetMethod("ShowDialog")
_result = method.Invoke(_manageComplexProperties, New Object() {_parentForm})