FAQ

[Struts-user] AJAX file upload

Frank W. Zammetti
Dec 1, 2010 at 3:20 pm

On 12/1/2010 9:00 AM, Robert Graf-Waczenski wrote:
Am 30.11.2010 21:59, schrieb Harsh C:
How can I setup a AJAX-ified file upload page using Struts 2? If
there is
some integration with Dojo, it would be even better i.e. not use the OS
specific file upload button etc.
There are various resources floating around in the net regarding "AJAX
file upload". Strictly speaking, there is no such thing as an "ajax
file upload" to begin with. If your web app needs to upload a file,
there are two choices: Either you use <input type="file"> in all its
ugliness (or beauty, if you put effort into styling the control
properly), or you implement a (signed) Java applet to grab the file
from your client's disk and upload it to the server.

That being said, i would still suggest to google for "AJAX file
upload" because some of the resources that you can find are actually
quite useful and describe a solution to the problem that your web app
may have here and there, namely that you have an html form on your
page already and that you now need an extra form (on a popup dialog,
layer, whatever) that can be submitted while the original form is
*not* (or not yet) submitted. For this, ajax comes into the picture:
It allows you to handle a separate HTTP submit roundtrip to accept the
uploaded file, do some validation with it and show the appropriate
errors on your popup dialog when the rest of the other form has not
yet been submitted.

And, finally: All this has nothing to do with Struts specifically.

Robert
FYI, DWR v3 has a super-sweet implementation of an "AJAX upload".
Doesn't solve the look-and-feel "issue" WRT the button, but if you want
to really be fooled into thinking you're actually using AJAX to do an
upload (because Robert is 100% right that there isn't actually such a
thing) than DWR v3 will make you smile as you write the 2-3 lines of
code you need :)

--
Frank W. Zammetti
Author of "Practical Palm Pre webOS Projects"
and "Practical Ext JS Projects with Gears"
and "Practical Dojo Projects"
and "Practical DWR 2 Projects"
and "Practical JavaScript, DOM Scripting and Ajax Projects"
and "Practical Ajax Projects with Java Technology"
(For info: apress.com/book/search?searchterm=zammetti&act=search)
All you could possibly want is here: zammetti.com


---------------------------------------------------------------------
To unsubscribe, e-mail: user-unsubscribe@struts.apache.org
For additional commands, e-mail: user-help@struts.apache.org
reply

Search Discussions

Discussion Posts

Previous

Follow ups

Related Discussions