Question

I have a data uri in memory that I would like the user to download.

This fiddle works in chrome but not FF: http://jsfiddle.net/6W2TY/

When you click run it will download the tiny image in chrome and do nothing in FF. Can anyone help me understand why it doesn’t work in FF and what I need to do to make it work?

Thanks!

Answer 1

You are using the new (html5) download attribute. As far as I know this is only supported in Chrome and not (yet) in Firefox.

Update 3-2018
This feature is now supported in almost all major browsers (No IE support).

Alternative: Using location.href

Another way to force a download is to redirect the user to the image like this:

// generate the image
var img = ""

// then call a function maybe onClick or something
downloadImage(img);

function downloadImage(data) {
    location.href = "data:application/octet-stream;base64," + data;
}

Or the short version

location.href = "data:application/octet-stream;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAOCAYAAAAmL5yKAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAABWSURBVDhPY0xISPh//0UOA7mAiVyNMH2jBjAwkBQGjD9KGBTEJ6OEO0kG2NvbMwCjnXwDsEU5SS5ANuDhjRCGJbPFSQsDdBfIyMhQZgDIQLK9QLWkDABPsQw5I+5qmAAAAABJRU5ErkJggg=="

Alternative: Server Side

As an alternative, if you are processing the image serverside you can force a download by setting the content-disposition header.

PHP Example

header('Content-Disposition: attachment; filename="image.png"');