An ASP.NET CAPTCHA Server Control

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8

Looks like the MSDN URL has changed; I suspect it refers to this (very good) article:

<a href="http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnaspp/html/hip_aspnet.asp">http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnaspp/html/hip_aspnet.asp</a>

This is based upon the .NET 1.x framework.

Regards, Matt

9

For me, I have found that the control doesn’t work when it resides on a page that uses master pages. When the control is on a basic *.aspx page, it works fine. However, the site I want to use this with uses master pages. Can you help me to understand why that may be?? In laymen’s terms as well. I am not a code guru.

10

I have solved my problem. There was a CSS conflict with my stylesheet and the styles applied to the DIV/SPAN elements within the control itself. It was also only an IE 6 bug as well. I stripped out all of the styles from your control and it worked with my stylesheet!

11

Very nice! and very helpful. I shall use it in my .net projects.
thanks

12

Nice work, Jefferson.

Why did you choose not to use it on codinghorror.com?

13

The 2.0 project download on The Code Project is missing the CaptchaImage.aspx file.

14

12w21w21

15

One question and one comment…

First, great control! You saved me a ton of time. =)

Now, for the question…

I’m using your controlw ith a Template version of the Login control. Unfortunately, the control appears to not have any events that fire upon failure. I would to display a simple error to my user when they make a typo in the CAPTCHA.

Any thoughts or recommendations?

19

Hi,

It is a great control and i am using it in a project.

The only problem is sometime the CAPTCHA image can not be displayed and i have to re-start IIS.

Please help.

Thanks

21

anyone happen to have a C# version?
Tx…

22

where is source code of this control…
and runtime files…

23

Where’s the source code? The link is broken!

24

There is an AJAX compatible version here: http://www.centrifugalbumblepuppy.com/posts/telerik-ajax-compatible-captcha-control.aspx

28

Hi, thanks for the article; in fact I used your render idea to integrate it into a fully featured control http://www.sharppieces.com/free-aspnet-controls/CaptchaImage.aspx. The control is open source on codeplex, check it out if you have time.

30

hola a todos buen blog
Entrar a esteblog es interesante

31

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32

For windows vista, you have to add:

add name=CaptchaImage path=CaptchaImage.aspx verb=GET type=WebControlCaptcha.CaptchaImageHandler resourceType=Unspecified preCondition=integratedMode /

in handlers section.

Regards,
Asang Dani

33

Implementation of Custom web control to display CAPTCHA image can be found here:

http://etechplanet.com/post/2009/05/11/Create-CAPTCHA-Image-using-C-and-ASPNet.aspx

35

Cool stuff, thanks. I’m actually thinking of wrapping this up in a DotNetNuke module, if it’s ok with you.

36

If you want a simple Captcha in asp.net, check this article: http://www.massimilianobianchi.info/max/20art_A-simple-CAPTCHA-with-ASP-NET.aspx