Muddy Coder <cosmo_gene...@yahoo.com> wrote: > Nowadays some websites let users to fill in some so-called > verification code, and the tricky thing is that the CODE is delivered > from server with an image. For example: > > <img src="/jobsearch/captcha.jpg" name="CAPTCHA_IMAGE" border="1" / > > <a href="#" onClick="changeSource();">Refresh Image</a> > > When click Refresh Image, the CODE on the image changes. I wonder: > does the server really send a new image over to browser, or just send > a hidden code over? Is it possible to parse out such hidden code? > > The other example is: > > <img src="/images/verify.png;jsessionid=ahZsBmwyLGuf" alt="Digital > Signature Code" /> > <input name="jsessionid" type="hidden" value="ahZsBmwyLGuf" /> > > I did a few REFRESH on browser, and noticed the CODE changed. But, > when I viewed the HTML source code, the value "ahZsBmwyLGuf" remained > the same. What is the trick around here? That is why I am wondering > whether the server really keeps sending new images over, or just > sending new hidden codes over. If the trick is just keep sending > hidden codes over, there might be a chance of capturing the codes. Can > somebody help me out? Thanks a lot!
If there were some way for a program to extract the code from what the server sent, then the whole point of using the Captcha (preventing spam robots from posting) would be defeated. --RDM -- http://mail.python.org/mailman/listinfo/python-list