How can I code my web page to download a file from a site visitor's computer?

Question

I am creating a html5 and javascript web page that allows you to draw your own picture. The page itself works, but I want to make it so my web application will create a folder in their Appdata (or Application Data if they're on a mac) directory.

Then I also want to make it so when a user logs back on to the website, all of their work is saved and they can pick up where they left off.

So basically, I want to be able to create a file on a client's directory, then be able to download that file once they have saved a change to their drawing. Is there a way I can do this? Thanks.

Answer 1

All of these things can be done by using the HTML5 file APIs. Here are some links which will help you with your task:

• http://www.html5rocks.com/en/tutorials/file/dndfiles/
• http://www.html5rocks.com/en/features/file_access

Storing state can be accomplished by using one of the following technologies:

• Cookies
• localStorage
• indexeddb
• WebSQL