RE: [WEB400] CGIDEV2 Problems

["Goodbar, Loyd (AFS-Water Valley)" <LGoodbar@xxxxxxxxxxxxxx>]

You are hitting a "feature" of how web browsers work. At least in Internet
Explorer, you can refreshed a "posted" form. Unless you have something
server side in your application that ensures "double posting" doesn't occur,
there isn't a good way to prevent people from 1) using their back button to
repost the form or 2) hitting refresh after the form is posted.

The web browser would need to be programmed to "ignore" refresh when it was
the result of posting a form. I don't know if any web browser does this.
This still doesn't protect you against the user hitting the back button then
and reposting the form.

The HTTP server itself doesn't "know" that a form was already posted, due to
the stateless nature of HTTP transactions. Again, the datastream is
"correct" to the web server. You might try generating a unique number for
the form on presentation, ensure the transaction from that form with that
unique number is only posted once. If this is a static form (not generated
from a program), there is nothing you can do due to the reasons above. I
believe this is an application-side issue rather than a HTTP server or
browser issue.

HTH,
Loyd

-----Original Message-----
From: Justin Houchin [mailto:justin@RELIATEK.COM]
Sent: Wednesday, August 28, 2002 7:09 AM
To: web400@midrange.com
Subject: [WEB400] CGIDEV2 Problems


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Hi Everyone,
            I am writing a program that will let the user view a customers
order by inputting there order number. Once in the order, the user will be
able to add comments to the order. I think my problem lies in the HTTP
datastream. Whenever I hit the refresh button on my browser, the program
will run again using the values that are still in the datastream. I don't
need this. It needs to be empty everytime the program runs. I have tried
doing a clear on the SavedQueryString and NbrVars. Same problem. I receive
the data into my program via ZhbGetVar. You can view my source code here..
http://www.reliatek.com/cgidev2p/dspsrc.pgm?cgiinp01=rtektest
<http://www.reliatek.com/cgidev2p/dspsrc.pgm?cgiinp01=rtektest&cgiinp02=
qrpglesrc&cgiinp03=orderinq> &cgiinp02=qrpglesrc&cgiinp03=orderinq
Please Help!!!

Justin Houchin
Programmer and Web Developer
ReliaTek, Inc
justin@reliatek.com