To test reference type variables for Nothing values, use the Is operator or the IsNot operator. : ByRef « Language Basics « VB.Net

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To test reference type variables for Nothing values, use the Is operator or the IsNot operator.

  

Module Module1
    Sub Main()

        Dim testObject As Object
        testObject = Nothing

        Console.WriteLine(testObject Is Nothing)

        Dim tc As New TestClass
        tc = Nothing

        Console.WriteLine(tc IsNot Nothing)
    End Sub

    Class TestClass
        Public field1 As Integer
        Dim field2 As Boolean
    End Class
End Module

   
    
  

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