Create and trigger custom event using the WPF webbrowser control

Question

It's relatively straightforward to create and fire a custom event in JavaScript. I'm trying to do the same in the WPF WebBrowser control. My naive approach:

    private void FirePreviewUpdateEvent()
    {
        var doc4 = (IHTMLDocument4) WPFBrowser.Document;
        if (doc4 == null) return;
        object eventObject = doc4.CreateEventObject(null);
        doc4.FireEvent("onpreviewupdated", ref eventObject);
    }

eventObject returns a valid ComObject , but firing the event throws an ArgumentException with a message that an argument is out of range (doesn't say which argument). What have I done wrong?

Answer 1

Well, it took more than a few hours, but I found this works:

private void FirePreviewUpdateEvent()
{
    dynamic doc = Browser.Document;
    var ev = doc.createEvent("event");
    ev.initEvent("previewUpdated", true, true);
    doc.dispatchEvent(ev);
}

I'm holding out something that utilizes the published IHtmlDocument interfaces since methods like initEvent are deprecated. If anyone has insight on this please do share.