Using IHTMLElementRender::DrawToDC is the wrong way to draw the contents of an webpage to a device drawing context. The reason why the IHTMLElementRender interface is not good is because it does not draw opacity or transpancy that might be visible in a web page. Instead it is best to query the IViewObject interface from the IHTMLDocument2 interface and call the function Draw.

BAD
IHTMLDocument2 — IHTMLElement – IHTMLElementRender::DrawToDC.

GOOD
IHTMLDocument2 – IViewObject::Draw using DVASPECT_DOCPRINT

You can also use OleDraw instead of IViewObject::Draw and pass OleDraw the IHTMLDocument2 interface.

This entry was posted on Friday, June 9th, 2006 at 9:22 pm and is filed under COM, Programming. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.