Null object

Hey guys,
How is it possible in VB .net to check whether an instance of a class has a null value or not, i.e. wht we used to do in VB6 was IsNull(objectName). I know bout IsDbNull() method in VB .net that is supposed to work just like IsNull() of VB6 but that hasnt helped me in my case. Need an answer quick.
Thanx in advance.

Awais Malik

Code:

---

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim obj As Object
        obj = System.DBNull.Value '/// make obj null

        MsgBox(IsDBNull(obj))
    End Sub

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that works like IsNull in vb6 :)