Q: Default values of HTML checkbox input

[Bart_Stutton]

I saw the answer to this question in the PHP manual once but cannot find it anywhere on their site now.

What are the default values of the variables generated by PHP for both a ticked checkbox and an unticked checkbox when a form is submitted to PHP?

[Bart_Stutton]

I found the answer in the HTML 4.01 spec. It says an unticked checkbox cannot be "successful" - i.e., it will not be submitted with a form. Therefore, the attached script works by detecting the presence of a PHP variable named for the checkbox.