I want to replace the standard system open file dialog with the one I wrote, that means no matter within which programs you are opening a file, my dialog will be shown instead of the standard one, is this possible?

It seems that that there is no such API provided to accomplish this, is it possible to use some hooking technique, but this has to be reliable and not to be treated as spyware by anti-virus tools?

any other options?

If this is not possible, is it possible to add to the spacebar or toolbar in the standard open file dialog a button which invokes my dialog, which allow users select a file and in turn returns the path of the selected file to the "File name" input box of the standard dialog?

Any hits, links and code examples will be appreciated.