Create and write to a file with javascript

Question

On the client side I want to:

1. Generate random data up to a specified size (ex: 1Mb or 512Kb).

2. Write that data into a file.

3. Post that file to an endpoint on my server with an AJAX request.

I know #1 is possible, but I'm not sure how to do it. I'm not sure if #2 is possible; I've heard that Chrome currently supports the full HTML5 file API, but I need a solution that works on mobile browsers too (iOS Safari, Android, etc). #3 is easy and I already know how to do it (I included it for clarity about what I'm trying to do).

Answer 1

I agree with with sending data with post, but if you really want to create a file and then send it, you should read this question:

How to give a Blob uploaded as FormData a file name?