Again, you might like to open the source code for this form in a separate window, so that you can refer to it as we talk you through.
Like our previous example, this page has a form called start at zero (for the first option).
If the user has not completed more than one field, then they will see an alert box appear for each field that is missing.
Now you know how to write a form validation script that can handle multiple form fields, including text boxes, radio buttons, drop-down lists and check boxes!
Our example is very simple as it only checks one field.