Private Sub WebView_JSDialog(sender As Object, e As JSDialogEventArgs)
        Select Case e.DialogType
            Case JSDialogType.Prompt
                'Create a dialog
                Dim dlg As New JSPrompt(e)
                dlg.Owner = Me
                dlg.Message = e.MessageText
                dlg.Value = e.DefaultPromptText

                'Display the dialog for user input
                Dim result As Nullable(Of Boolean) = dlg.ShowDialog()

                'Call e.OK/e.Cancel based on whether user clicked "OK" in the dialog
                If result.HasValue AndAlso Not result.Value Then
                    e.OK(dlg.Value)
                Else
                    e.Cancel()
                End If
                Exit Select

            Case JSDialogType.Alert
                'Display a message box and then call e.OK to notify the browser
                'engine that user has confirmed the dialog. This is important
                'because either OK or Cancel must be called to prevent the default
                'dialog
                MessageBox.Show(e.MessageText, "JavaScript Message", MessageBoxButtons.OK)
                e.OK()
                Exit Select

            Case JSDialogType.BeforeUnload, JSDialogType.Confirm
                'Display a Yes/No message box and call e.OK/e.Cancel according
                'to user's selection
                If MessageBox.Show(e.MessageText, "JavaScript Message", MessageBoxButtons.YesNo) = MessageBoxButtons.OK Then
                    e.OK()
                Else
                    e.Cancel()
                End If
                Exit Select
        End Select
    End Sub