PHP: Reloading the captcha image from javascript

Question

I have a user registration form in PHP .I put captcha image check in the page.I used it like this

<img src="captcha.php" alt="Enter this text in the adjacent text box" id="imgCaptcha" />

and in my javascript i will validate this with the same number which is generated in the image (from captcha.php page) . That number was set in a session variable too. Now i want to reload the image to another image from my javascript , if the validattion fails .Is there any way to do so ?

In my captcha.php page,I am creating a Number randomly and then creating an image using imagejpeg. I set this number (in the image) to as session varible also

Please guide me to solve this

Thanks in advance

you probably want to change the Alt attribute to Title. Alt text will be displayed in case the image can't be loaded, or the user specifically disabled image loading. In that case, the user will not be able to read the captcha image and enter anything in the adjacent text box. Or do you actually want the user to enter "Enter this text in the adjacent text box" into the text box? (I know you don't, but that's how confusing it could get if you use Alt instead of Title) — Peter Perháč
– Peter Perháč, Commented May 16, 2009 at 9:01

karim79 · Accepted Answer · 2009-05-16 08:36:53Z

5

You need to inject captcha.php into the page using ajax. There are several ways to do this:

javascript using XHR but this can be a pain. Here is an example.
jQuery provides a simple way to do this, for example:

$('#someButton').click(function() { $('#someDiv').load('captcha.php'); });
prototype.js is a bit more verbose, but does the job. Example.

I would suggest using jQuery, there are great examples in the docs.

If your registration page returns on a validation error, you do not need to use javascript for the captcha to get reloaded, that should happen automatically.

answered May 16, 2009 at 8:36

karim79

343k67 gold badges420 silver badges409 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Peter Perháč Over a year ago

awesome answer. +3 (oh, but only one counts ;))

Collectives™ on Stack Overflow

PHP: Reloading the captcha image from javascript

1 Answer 1

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related