Network_Manager.Gadget.ControlPanel.Routes.SavedRoutes.UnloadForm.defaultInterfaceMode_SelectedIndexChanged C# (CSharp) Method

        private void defaultInterfaceMode_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (defaultInterfaceMode.SelectedIndex == 0)
            {
                if (unloadIPv4 > 0 && NotActiveIPv4Routes > 0)
                {
                    tabControl1.TabPages[0].Enabled = true;
                    button1.Enabled = true;
                    if (unloadIPv6 == 0 || NotActiveIPv6Routes == 0)
                        tabControl1.SelectTab(0);
                }
                else
                {
                    tabControl1.TabPages[0].Enabled = false;
                }
                if (unloadIPv6 > 0 && NotActiveIPv6Routes > 0)
                {
                    tabControl1.TabPages[1].Enabled = true;
                    button1.Enabled = true;
                    if (unloadIPv4 == 0 || NotActiveIPv4Routes == 0)
                        tabControl1.SelectTab(1);
                }
                else
                    tabControl1.TabPages[1].Enabled = false;
            }
            else
            {

                if (unloadIPv4 > 0)
                    tabControl1.TabPages[0].Enabled = true;
                else
                    tabControl1.TabPages[0].Enabled = false;
                if (unloadIPv6 > 0)
                    tabControl1.TabPages[1].Enabled = true;
                else
                    tabControl1.TabPages[1].Enabled = false;
            }
            if (unloadIPv4 == 0 && unloadIPv6 == 0)
            {
                tabControl1.TabPages[0].Enabled = false;
                tabControl1.TabPages[1].Enabled = false;
                button1.Enabled = false;
            }
            else
                button1.Enabled = true;
        }