ExecuteScalar sql

Dim conex As String =""
Dim con As New SqlConnection(conex)
Try
Dim query As String=""
con.Open()
 Using cmd As New SqlCommand(query, con)
                cmd.Parameters.Add("@id", SqlDbType.Int).Value = TextBox.Text
                id_adjunto_IN = cmd.ExecuteScalar()
            End Using
con.Close()
Catch ex As Exception
con.close()
End Try