This web page is a demo showing most HTML form inputs with the
simplest possible front-end code. Fill out any fields you please, press the Validate button, and any errors will be reported in the scrolling text box at the bottom of the page. Requiring only a hook on the submit button,
this front-end validation provides immediate user feedback.
You may enable diagnostics on the front-end processing by providing a value for the diagnostic mask (next to the Validate button). This will pop-up a new window with formatted and color-coded diagnostics.
For back-end validation, select the Submit to Server option. Then, the same validation engine on the server will return its results on a fresh web page. (Normally, you would not want to proceed with server-side processing while the client-side engine detects errors. But in this CleanCode-engineered setup, if the client-side is error-free, the server-side will also be error-free.)