Reading A Local File, Encoding To Base64, I Would Like To Give The User An Option To Save The Result To File

I have a webpage encoding a local file into Base64, and would like to give the user an option to save the result - now residing in a html element - without going back to the server

Solution 1:

You could do it like this:

var file = //your Base64 encoded filevar url = 'data:application/octet-stream;base64,' + file;
window.open(url);

You should adapt the code so the mime type matches the content you are serving (application/pdf...)

To pass a file name you will have to use a anchor tag like follows :

<ahref="data:application/octet-stream;base64,/*YOUR FILE DATA*/"download="your filename">

but this is not crossbrowser. See http://updates.html5rocks.com/2011/08/Downloading-resources-in-HTML5-a-download