Sep 29, 2010 Introduction Before I jump into the code to add a captcha to an HTML contact page, I would to answer the question on what a captcha actually is. Home › Contact Forms › HTML contact form with CAPTCHA. HTML contact form with CAPTCHA. Posted on March 14. Here is the HTML code for the contact form.

We will generate two random numbers and sum them together, then user must do the math and write the answer in a text field. He will be redirected to another page where the sum of the two random numbers is calculated and compared with his answer. If the sum is correct, form will be submitted, but if the sum is wrong it will output an error message. Full HD Video Tutorial Preparing the Files For this tutorial we will need 2 php files. One will contain the form with the simple php captcha and one will contain the code to validate what user has typed in the captcha field. Create Variables with Random Numbers for Our Simple PHP Captcha First of all we will need to create 2 variables, one with a minimum number and one with a maximum number. Then you will need another 2 variables that will generate random numbers between the range of the minimum and maximum numbers created earlier.

Below is the PHP code: Display Generated Numbers to Users Now that we have our numbers we need to echo (display) them to our users, so they can resolve the simple php captcha code. Also you will need to add a simple text input, giving a name attribute to retrieve inside a variable what user has typed in. After the user will fill the results, he will click the submit, then he will be redirected to another php file where we will validate the simple php captcha. To do that we will need to create 2 hidden inputs on the initial page, each field with his generated number. Hidden inputs are not visible in page and can be used in php to store data inside variables, same as a regular text input. Casio Dw-5200 Manual. Kd Tripathi Pharmacology Pdf. You can read more about input's type attribute, including hidden attribute.