Invoking SaveAs Dialog Box

I have disabled the IE menu bar and toolbar, and I'm using the document.execCommand("SaveAs",false,".htm") command to allow users to save the ASP pages as html files.

I noticed that the execCommand doesn't save the exact copy of the page (e.g. missing images, no CSS). Is there another command that will work exactly like the File, Save As... from the IE menu bar?

I'm using an external CSS and when I use the execCommand, my styles are all gone.