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<Input type="file"...>

it will let the user to click to "browse" button to browse for files,
question is how can I limit the file type to be only jpg and gif extension,
when the browse window open ?

thank you.



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Nope, not a widely supported anyway, I seem to remember some browser  =

specific options, but they don't play nice together. If this is a must, =

look into a flash (or possibly java) uploader, which can be more  =

controlled (varying from just type to selecting while directories/mulitp=
le  =

files at once). Be sure to provide a clean HTML fallback.
-- =

Rik Wasmus


On Thu, 21 Feb 2008 19:56:26 +0100, Rik Wasmus  
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...varying from just extensions, to selecting whole directorie.
Rik Wasmus


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accept = content-type-list [CI]
    This attribute specifies a comma-separated list of content types
that a server processing this form will handle correctly. User agents
may use this information to filter out non-conforming files when
prompting a user to select files to be sent to the server (cf. the
INPUT element when type=3D"file").


<input type=3D"file" accept=3D"image/jpg, image/gif">

Not tested.



GTalbot wrote:
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The operative word is "may" and *none* of the browsers I have FF,
SeaMonkey, Opera, IE and old Netscape do.

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The only way check at the receiving server side script. You can use the
option of additionally prescreening the selection with JavaScript.

Take care,


On Thu, 21 Feb 2008 15:19:30 -0800 in GTalbot

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This seems to rely on MIME types (amongst other things), so in principle
could I send a file abc which is encoded as a gif or jpeg and have it
accepted? If the string above worked and no others, what of image/jpeg or
image/jpe - are these also encoded by the same codex? To the strict
letter of the OP, perhaps all you need to do is check the last three
letters of the filename, but that may run into issues with things like
def.gif which is actually an executable..?


Stephan Bird MChem(Hons) AMRSC
Currently in Caernarfon, Wales.


Scripsit Stephan Bird:

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MIME types would be the right concept to be used, but as Jonathan
mentioned, this attribute has not been implemented. There's a lot in
file input that exists only in the original plans and later
specifications and was ignored or distorted by implementors; see

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In principle, yes. However, image/jpg is an unregistered MIME type; this
was probably a typo, and image/jpeg was intended. If image/jpg were
actually used, it would be ignored by a conforming implementation, and
GIF images only would be accepted.

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The correct MIME type name is image/jpeg, and image/jpg and image/jpe
are undefined and to be ignored. However, a quality implementation would
issue a warning and prompt the user for corrective action and send a
message to the page author, if specified in metadata, and then cows
would fly.

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The last three letters of a filename are no magic. Programs may assume
some mapping from them to MIME types, but there is no specification on
this, and there is great variation in practice.

A proper implementation of accept="..." would require, more or less, a
file system where each file has a descriptor indicating its properties,
such as MIME type (and character encoding, etc.). Simple filtering by
filename extension would be easy to implement but somewhat problematic;
in practice, implementors just didn't bother.

Jukka K. Korpela ("Yucca")

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