Re: How to draw on "Microsoft Web Browser" control?

Currently I am using IHTMLElement::get_style method to do that. The
code:

void CTestMSHTMLDlg::HightlightSingleElement(long sourceIndex){
    static long lastSourceIndex = -1;
    static BSTR lastBorderWidth, lastBorderColor;

    //////////////////////////////
    HRESULT hr;
    IDispatch * pDisp1, * pDisp2, * pDisp3;
    MSHTML::IHTMLDocument2 * pDoc;
    MSHTML::IHTMLElementCollection * pCollection;
    MSHTML::IHTMLElement * pElement1, * pElement2;
    MSHTML::IHTMLStyle * pStyle1, * pStyle2;
    VARIANT varIndex;
    varIndex.vt = VT_UINT;
    VARIANT var2;
    VariantInit(&var2);

    //////////////////////////////
    pDisp1 = this->m_webBrowser.GetDocument();
    hr = pDisp1->QueryInterface( IID_IHTMLDocument2, (void **) &pDoc);
    if(SUCCEEDED(hr)){
        hr = pDoc->get_all(&pCollection);
        if(SUCCEEDED(hr)){
            //cancel last highlight
            if(lastSourceIndex != -1){
                varIndex.lVal = lastSourceIndex;
                VariantInit(&var2);
                pDisp3 = pCollection->item(varIndex, var2);
                hr = pDisp3->QueryInterface(IID_IHTMLElement, (void **)&pElement2);
                if(SUCCEEDED(hr)){
                    hr = pElement2->get_style(&pStyle2);
                    if(SUCCEEDED(hr)){
                        pStyle2->put_borderColor(lastBorderColor);
                        pStyle2->put_borderWidth(lastBorderWidth);
                    }
                }
                pStyle2->Release();
                pElement2->Release();
                pDisp3->Release();
            }

            //cast new highlight
            varIndex.lVal = sourceIndex;
            VariantInit(&var2);
            pDisp2 = pCollection->item(varIndex, var2);
            hr = pDisp2->QueryInterface(IID_IHTMLElement, (void **)&pElement1);
            if(SUCCEEDED(hr)){
                hr = pElement1->get_style(&pStyle1);
                if(SUCCEEDED(hr)){
                    //update lastSourceIndex, lastBoderColor, lastBorderWidth
                    lastSourceIndex = sourceIndex;
                    pStyle1->get_borderColor(&lastBorderColor);
                    pStyle1->get_borderWidth(&lastBorderWidth);
                    //cast
                    pStyle1->put_borderColor(CComBSTR("red"));
                    pStyle1->put_borderWidth(CComBSTR("thick"));
                }
            }
        }
    }

    //////////////////////////////
    VARIANT varargStart;
    varargStart.vt = VT_BOOL;
    varargStart.boolVal = true;
    pElement1->scrollIntoView(varargStart);

    //////////////////////////////
    pStyle1->Release();
    pElement1->Release();
    pDisp2->Release();
    pCollection->Release();
    pDoc->Release();
    pDisp1->Release();
}

I don't know the difference between IHTMLElement2::get_runtimeStyle()
and IHTMLElement::get_style, but my experience with
IHTMLElement::get_style is that it only works for image
element(<img...>).
What I need is to draw a rectangle to encompass one or several
elements, but this method only works for single image element. And
there are always enough invisible elements(<script...>, <!...>, etc) to
make this method insufficient for me.