Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
    Handles button1.Click

    If radioButton1.Checked Then
        Application.VisualStyleState = _
            VisualStyleState.ClientAreaEnabled
    ElseIf radioButton2.Checked Then
        Application.VisualStyleState = _
            VisualStyleState.NonClientAreaEnabled
    ElseIf radioButton3.Checked Then
        Application.VisualStyleState = _
            VisualStyleState.ClientAndNonClientAreasEnabled
    ElseIf radioButton4.Checked Then
        Application.VisualStyleState = _
            VisualStyleState.NoneEnabled
    End If

    ' Repaint the form and all child controls.
    Me.Invalidate(True)
End Sub

        void button1_Click(object sender, EventArgs e)
        {
            if (radioButton1.Checked)
            {
                Application.VisualStyleState =
                    VisualStyleState.ClientAreaEnabled;
            }
            else if (radioButton2.Checked)
            {
                Application.VisualStyleState =
                    VisualStyleState.NonClientAreaEnabled;
            }
            else if (radioButton3.Checked)
            {
                Application.VisualStyleState =
                    VisualStyleState.ClientAndNonClientAreasEnabled;
            }
            else if (radioButton4.Checked)
            {
                Application.VisualStyleState =
                    VisualStyleState.NoneEnabled;
            }

            // Repaint the form and all child controls.
            this.Invalidate(true);
        }

private:
    void UpdateButton_Click(Object^ sender, EventArgs^ e)
    {
        if (applyToClient->Checked)
        {
            Application::VisualStyleState =
                VisualStyleState::ClientAreaEnabled;
        }
        else if (applyToNonClient->Checked)
        {
            Application::VisualStyleState =
                VisualStyleState::NonClientAreaEnabled;
        }
        else if (applyToAll->Checked)
        {
            Application::VisualStyleState =
                VisualStyleState::ClientAndNonClientAreasEnabled;
        }
        else if (disableStyles->Checked)
        {
            Application::VisualStyleState =
                VisualStyleState::NoneEnabled;
        }

        // Repaint the form and all child controls.
        this->Invalidate(true);
    }