Designer Events

[Designer(typeof(DesignerEventsDesigner))]
public class DesignerEvents : WebControl
{
}


public class DesignerEventsDesigner : ControlDesigner
{
    private string controlAddedID, controlRemovedID;
    private bool designerActive;

    public override void Initialize(IComponent component)
    {
        base.Initialize(component);

        //Hook our events
        HookDesignerEvents();
    }

    public override string GetDesignTimeHtml()
    {
        //Grab our control
        DesignerEvents control = (Component as DesignerEvents);

        //Check to see if our control has a width, if not set it.
        if (control.Width.IsEmpty) control.Width = 300;

        string html = "<div id='" + control.ID +"' style='height: " + control.Height
                    + "; width: " + control.Width + "'>ControlAdded: " + controlAddedID
                    + "<br>ControlRemoved: " + controlRemovedID
                    + "<br>DesignerActivated: " + designerActive.ToString()
                    + "</div>";
        return html;
    }

    public void HookDesignerEvents()
    {
        //Get the IDesignerHost
        IDesignerHost host = Component.Site.GetService(typeof(IDesignerHost)) as IDesignerHost;

        //Get the component event service
        IComponentChangeService componentService = host.GetService(typeof(IComponentChangeService)) as IComponentChangeService;

        //Hook our events
        host.Activated += new EventHandler(host_Activated);
        componentService.ComponentAdded += new ComponentEventHandler(componentService_ComponentAdded);
        componentService.ComponentRemoved += new ComponentEventHandler(componentService_ComponentRemoved);
    }

    void componentService_ComponentRemoved(object sender, ComponentEventArgs e)
    {
        controlRemovedID = e.Component.Site.Name;
        UpdateDesignTimeHtml();
    }

    void componentService_ComponentAdded(object sender, ComponentEventArgs e)
    {
        controlAddedID = e.Component.Site.Name;
        UpdateDesignTimeHtml();
    }

    void host_Activated(object sender, EventArgs e)
    {
        designerActive = true;
        UpdateDesignTimeHtml();
    }
}