BC32128: 'IsNot' operand of type 'typename' can only be compared to 'Nothing', because 'typename' is a nullable type

A variable declared as a nullable value type has been compared to an expression other than Nothing using the IsNot operator.

Error ID: BC32128

To correct this error

To compare a nullable type to an expression other than Nothing by using the IsNot operator, call the GetType method on the nullable type and compare the result to the expression, as shown in the following example.

Dim number? As Integer = 5

If number IsNot Nothing Then
  If number.GetType() IsNot Type.GetType("System.Int32") Then

  End If
End If

See also

• Nullable Value Types
• IsNot Operator