https://github.com/drufball/writable-files/ explores solutions to this problem.
Today, if a web site wants to create experiences involving local files (document editor, image compressor, etc.) they are at a disadvantage to native apps. A web site must ask the user to reopen a file every time they want to edit it. After opening, the site can only save changes by re downloading the file to the Downloads folder. A native app, by comparison, can maintain a most recently used list, auto save, and save files anywhere the user wants.
- Open local file to read
- Open local file to edit and then save
- Open local file to edit with auto save
- Create and save a new file
- Delete an existing file
- Read meta data about files
- FileSaver.js polyfills
saveAs()from the [W3C File API], but files open in a new window instead of downloading on Safari 6.1+ and iOS.
- In Edge, Firefox, and Chrome developers can:
- Create a fake anchor element
- Set the
downloadattribute to the desired filename
href:to a data URI
- Faking a click on the anchor element
'data:application/octet-stream' + data_stream
- Hidden Flash controls to display a “save as” dialog
These methods are clunky and only support “save as”. They do not support most recently used lists, auto save, save, or deleting a file.