Restrict attaching big files using Javascript.

Question

Hi All,

How can we restrict users from attaching file bigger than specified size (to say 20MB). I do have a check at the server side to show errors in case of big files received on the server but that happens too late.

I want to achieve something like gmail, where you get a quick alert specifying

"This file exceeds the 25MB attachment limit. Sorry."

Thanks!

Pratik

Answer 1

Javascript does not have access to this kind of information, but a tool like swfupload can give you nice javascript api's to access this information with flash.

http://swfupload.org/

Answer 2

Use JQuery File Upload plugin.

Answer 3

In general, JavaScript should not be used for any restrictions of user actions since it is executed on the client side and can be manipulated. Flash suffers from the same problem.

Any restrictions should be implemented on the server side.