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Re: How to validate a file in a javascript

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Jeff North wrote:

> A couple of years ago I too wanted to validate the filetype the
> visitor had selected before sending everything to the server. I
> couldn't even access the filename because of security restrictions.
> 
> It seems these days this restriction has been relaxed. I checked out
> https://developer.mozilla.org/en-
US/docs/Using_files_from_web_applications#Example.3A_Showing_file%28s%29_size
> This works in FF 16, Opera 12, sort of in works in Chrome 22, hardly
> works in Safari 5 and doesn't work in IE 9.
> 
> Also check out the WHATWG description of type=file -
> http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-
type-attribute.html#file-upload-state-%28type=file%29
> 
> So while there are some restrictions that have been lifted there is no
> standard implementation of the new rules. So I guess it is back to
> validating the file server-side.

The Good Thing about using client-side scripting is that in many cases you 
actually can have the cake and eat it.  This example is no exception.  You 
can validate forms both client-side and server-side, providing users with 
user agents where client-side validation is possible with the additional 
benefits of providing immediate feedback and avoiding unnecessary 
roundtrips.


PointedEars
-- 
When all you know is jQuery, every problem looks $(olvable).

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Thread

How to validate a file in a javascript Katja <kate.kokatjuhha@gmail.com> - 2012-10-28 11:56 -0700
  Re: How to validate a file in jquery Denis McMahon <denismfmcmahon@gmail.com> - 2012-10-28 21:11 +0000
  Re: How to validate a file in a javascript Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2012-10-28 22:38 +0100
    Re: How to validate a file in a javascript Katja <kate.kokatjuhha@gmail.com> - 2012-10-28 23:32 -0700
      Re: How to validate a file in a javascript Denis McMahon <denismfmcmahon@gmail.com> - 2012-10-29 08:57 +0000
        Re: How to validate a file in a javascript Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2012-10-29 15:20 +0100
          Re: How to validate a file in a javascript Denis McMahon <denismfmcmahon@gmail.com> - 2012-10-29 23:22 +0000
            Re: How to validate a file in a javascript Jeff North <jnorthau@yahoo.com.au> - 2012-10-30 17:11 +1100
              Re: How to validate a file in a javascript Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-11-01 21:51 +0100
        Re: How to validate a file in a javascript Dr J R Stockton <reply1244@merlyn.demon.co.uk.invalid> - 2012-10-30 19:47 +0000

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