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Re: How to validate a file in a javascript

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On Mon, 29 Oct 2012 15:20:33 +0100, Cezary Tomczyk wrote:

> W dniu 2012-10-29 09:57, Denis McMahon pisze:
>> On Sun, 28 Oct 2012 23:32:33 -0700, Katja wrote:
>>
>>>> I wouldn't trust on file extensions. As a just a warning for user
>>>> then
>>>>
>>>> it is ok. Just my "5 cents".
>>>>
>>> I know but I still need it =)
>>
>> Javascript has no direct access to the filesystem. Thus, it can not
>> reliably determine the size of a file. At best, you can do (sub)string
>> comparisons and regex checks against a file name entered into a form
>> field.
> 
> Not really. There is some possibilities. See:
> https://developer.mozilla.org/en-US/docs/
Using_files_from_web_applications
> 
> There is "but". File API must be implemented in browser.

I think it would be presumptuous for any javascript programmer to assume 
that he was going to have any access to the client filesystem unless he 
controlled the client. But I'll just knock up a page that will look in 
all your files when you visit my server ....

Even if the file api is implemented in the browser, any intelligent 
browser is going to provide a means to control its exposure to the web, 
and any sensible and security conscious user is going to lock it down as 
tightly as they can.

Rgds

Denis McMahon

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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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