WPF WebBrowser: How to set element click event?

I've figured out how to make everything red as soon as the page is finished loading:

private void webBrowser1_LoadCompleted(object sender, NavigationEventArgs e)
{
    var doc = (IHTMLDocument2)webBrowser1.Document;
    foreach (IHTMLElement elem in doc.all)
    {
        elem.style.backgroundColor = "#ff0000";
    }
}

Now what if I want to make the element only change color when it's clicked? I see that elem has an onclick property, but it's type is dynamic so I don't know what to do with it. The documentatio开发者_如何学运维n is pretty useless.

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You could do it by using the HTMLDocumentClass instead of the IHTMLDocument2 interface:

public partial class Window1 : Window
{
    public Window1()
    {
        InitializeComponent();
    }

    private void webBrowser1_LoadCompleted(object sender, NavigationEventArgs e)
    {
        mshtml.HTMLDocumentClass doc = (mshtml.HTMLDocumentClass)webBrowser1.Document;
        doc.HTMLDocumentEvents_Event_onclick += new mshtml.HTMLDocumentEvents_onclickEventHandler(OnClickHandler);
    }

    bool OnClickHandler()
    {
        mshtml.HTMLDocumentClass doc = (mshtml.HTMLDocumentClass)webBrowser1.Document;
        mshtml.IHTMLWindow2 win = doc.parentWindow;
        win.@event.srcElement.style.backgroundColor = "#ff0000";
        return false;
    }

}

The above solution, has one drawback: the onclick event does not bubble, even though false is returned (i.e. clicking at hyperlinks does not navigate to other pages).