BHO HtmlEventObject崩溃

VARIANT_BOOL STDMETHODCALLTYPE OnHelp(IHTMLEventObj2 *pEvtObj)
{
    std::cout << \"OnHelp Event\" << std::endl;

    if(pEvtObj != NULL) {
        VARIANT var;
        pEvtObj->getAttribute(L\"formID\", 0, &var);
        std::cout << (char*)var.bstrVal << std::endl;
    } 
    else {
        std::cout << \"PELEM = NULL\" << std::endl;
    }

    return VARIANT_TRUE;
}

VARIANT_BOOL STDMETHODCALLTYPE OnHelp(IHTMLEventObj *pEvtObj)
{
    IHTMLEventObj2 *pEvtObj2;
    pEvtObj->QueryInterface(IID_IHTMLEventObj2, (void**)&pEvtObj2);

    if(pEvtObj2 != NULL) {
        VARIANT var;
        pEvtObj2->getAttribute(CComBSTR(L\"url\"), 0, &var);
        std::cout << _bstr_t(var.bstrVal) << std::endl;
    } 
    else {
        std::cout << \"PELEM = NULL\" << std::endl;
    }

    return VARIANT_TRUE;
}