Type '<typeName>' must be a value type or a type argument constrained to 'Structure' in order to be used with 'Nullable' or nullable modifier '?'
Only value types, including structures, can be declared nullable.
' Valid.
Dim n? As Integer
Dim m As Integer?
' Not valid.
' Dim p? As Object
' Dim q As Nullable(Of Object)
Error ID: BC33101
To correct this error
Remove the '?' or Nullable.
Use a value data type.