Note This feature is supported by version 19.5. or greater Note The code uses some of the objects defined in The Business Layer. Since version 19.5, The GroupDocs.Assembly provides a great feature which is saving of external resource Files while an assembled document loaded from a non-HTML format is being saved to HTML.
From now on, when saving an assembled document to an HTML File, by default, external resource Files are stored to a folder having the same name as the HTML File without extension plus the “_Files” suffix....Merger Product Solution GroupDocs...Resource Files / Saving to HTML with External Resource Files Saving...