COM

<br />
        CComPtr< MSXML2::IXMLDOMDocument2 > m_spDoc;<br />

<br />
	MSXML2::IXMLDOMNodePtr pNewChild;<br />
	MSXML2::IXMLDOMElementPtr pDomElement;<br />
	CComPtr<msxml2::ixmldomelement> spDomElement;<br />
</msxml2::ixmldomelement>

public delegate void HtmlEvent(mshtml.IHTMLEventObj e);

[ComVisible(true)]
public class HtmlDocumentEventHandler
{
    private mshtml.HTMLDocument htmlDocument;

    public HtmlEvent eventHandler;

    public HtmlDocumentEventHandler(mshtml.HTMLDocument htmlDocument)
    {
        this.htmlDocument = htmlDocument;
    }

    [DispId(0)]
    public void Call()
    {
        this.eventHandler(this.htmlDocument.parentWindow.@event);
    }
}

[ComVisible(true)]
public class HtmlDocumentFormElement
{
    private mshtml.IHTMLFormElement element;
    private mshtml.HTMLDocument document;

    public HtmlDocumentFormElement(mshtml.HTMLDocument document, mshtml.IHTMLFormElement element)
    {
        this.document = document;
        this.element = element;
    }

    public event HtmlEvent onSubmit
    {
        add
        {
            object old = this.element.onsubmit;
            HtmlDocumentEventHandler handler = old is HtmlDocumentEventHandler ? old as HtmlDocumentEventHandler : new HtmlDocumentEventHandler(this.document);

            this.element.onsubmit = handler;
            handler.eventHandler += value;
        }
        remove
        {
            object old = this.element.onsubmit;
            HtmlDocumentEventHandler handler = old is HtmlDocumentEventHandler ? old as HtmlDocumentEventHandler : null;

            if (handler != null)
                handler.eventHandler -= value;
        }
    }
}

//Usage:

mshtml.IHTMLFormElement element = form as mshtml.IHTMLFormElement;
HtmlDocumentFormElement formElement = new HtmlDocumentFormElement(this.HTMLDocument, element);
formElement.onSubmit += new HtmlEvent(OnSubmitEventHandler);