[Zope] Image Upload detection

[Alexander Staubo]

There may be an easier way, but here's how I'm doing it.

In the DTML Method that is the target of the post, do something like
this (untested):

  <!--#if image-->
    <!--#call "REQUEST.image.seek(0, 2)"-->
    <!--#if "REQUEST.image.tell() > 0"-->
      <!--#call "REQUEST.image.seek(0)"-->
      <!--#call "manage_addImage(REQUEST.image.filename, file =
REQUEST.image)"-->
    <!--#/if-->
  <!--#/if-->

This will determine the file size of the file and if non-zero, will add
it to the current folder.

The second seek might not be necessary (it depends on whether
manage_addImage() or whatever you do with the file does it).

PS: It's multipart _encoding_, not encryption. Basically the browser
just base64 encodes the data and sends it as text. HTTP/MIME supports
the "binary" content transfer encoding for a multipart value, which is
roughly 12.5% more efficient compared to base64, although I have never
checked whether modern browsers support this.

--
Alexander Staubo             http://www.mop.no/~alex/
"`Ford, you're turning into a penguin. Stop it.'"
--Douglas Adams, _The Hitchhiker's Guide to the Galaxy_

>-----Original Message-----
>From: zope-admin@zope.org [mailto:zope-admin@zope.org]On Behalf Of Phil
>Grove
>Sent: 17. juni 1999 19:26
>To: zope@zope.org
>Subject: [Zope] Image Upload detection
>
>
>Hello all,
>
>second question of the day.
>
>Right, how do you detect if an image has been provided for upload when
>using the MULTIPART encryption method on a form?
>
>Basically, i have got a form that uploads three images to Zope
>and the user
>has the choice to upload between 1 and 3 pictures, so
>obviously, i need to
>check if the file boxes are empty or not. For example:
>
><INPUT TYPE="file" NAME="newImg">
>
>at the zope end:
>
><!--#if newImg-->
>  image is here
><!--#else-->
> nothing there matey boy
><!--#/if-->
>
>does not work.... any ideas on how to check???
>
>Please help, i am losing my hair very quickily....
>
>Cheers,
>
>P.
>
>---------------------------------------------------------------------
>
>Phil Grove	          phil.grove@flg21.com
>Web Development         0113 2949494
>flg21                   http://www.flg21.com
>
>---------------------------------------------------------------------
>
>
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