Add CAPTCHA Protection To Your Forms
... Prevent Spammer Robots from Using Your Forms! ...
Are your forms being abused by spam robots? Are you're tired of deleting hundreds of junk form submission emails in order to find one from a real person? Then you need to add a 'CAPTCHA' to your forms to protect them from spam and other abuse.
"CAPTCHA" is an acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart." It consists of a series of random images of letters or numbers in an image that must be entered correctly with the form submission to verify that a real person is submitting the form - not a spam bot.
Intersessions has added an easy-to-use FormtoMail with CAPTCHA CGI program to its Unix servers that any of our hosted websites can use. Just follow the instructions for our standard FormtoMail CGI with the following changes.
Form Action Command:
Use formtomail2.pl instead of formtomail.pl in your FORM ACTION command as follows:
<FORM METHOD="POST" ACTION="/cgi-bin/formtomail2.pl" ENCTYPE="x-www-form-encoded">
Display the CAPTCHA image:
After you've added all the elements for your form you need to create a place holder where the program can insert an image of a series of random numbers. Just add the following line to your html code:
<img src="/cgi-bin/captcha.pl" height=21 width=76>
Add the CAPTCHA input field:
Here's where the real person will enter the numbers he sees. Add this line to your form. Make sure the element has the name captcha:
<input type="text" name="captcha" >
If the user enters the correct number the form program will work as usual - the form results will be emailed to you. However, if the wrong number is entered the user will get a screen telling him that the number entered was incorrect and to try again.
The finished product:
Here's what your CAPTCHA should look like:
Note: If, after clicking on submit you hit the back button on your browser you'll need to refresh your browser in order to get a new CAPTCHA code. The old code cannot be used again.