A quick and good solution to add Captcha’s to your solution is to use Google’s. There are various solutions available online to make your own captcha, but I prefer usingGoogle’s Recaptcha which can be found on:http://www.google.com/recaptcha
There is this free usercontrol available online.
Here are the 10 easy steps to follow:
1) sign up at https://www.google.com/recaptcha/admin/create
2) add a site
3) copy & paste your public and private key in notepad as reminder
4) download and extract the latest version of the .net control which can be found athttp://code.google.com/p/recaptcha/downloads/list?q=label:aspnetlib-Latest
5) put the extracted files in the Bin folder of your solution
6) The next thing is to add a reference in your project to the DLL in your Bin folder.
7) Register the control in the page (or usercontrol) by adding this to the top of the page:
1 | <%@ Register TagPrefix="recaptcha" Namespace="Recaptcha" Assembly="Recaptcha" %> |
8) Insert the control in your aspx (or ascx) file at the right place
1 2 3 4 5 6 | <recaptcha:RecaptchaControl ID="recaptcha" runat="server" PublicKey="your_public_key" PrivateKey="your_private_key" /> |
9) Insert your public and private key which you stored with notepad.
10) Do not forget to validate the Recaptcha control. Here is how I did it in my code behind of an
1 2 3 4 5 6 | protected void Login1_LoggedIn(object sender, EventArgs e){ //LogVisit(); recaptcha.Validate(); if (recaptcha.IsValid) { // etc |
