The following example will create a contact form
Remarks
I started to write the contact form almost a year ago. It contained just text boxes and labels and nothing more to it. Waqar created a contact form as well, and I wanted to do the same thing, but with inherent Google Apps Script code. I ended up
using many different pieces of code.
  1. All input is validated through a clienthandler, when something changes (through the change handler).
  2. Only when the input is "OK", then the hidden textbox (createHidden doesn't seem to work) is set to contain a '1'.
  3. When all fields have valid entries, then the sum of those is validate, through validateSum (needs to have 4)
  4. Only then, the submit button is shown.
  5. The submit button, in combination with a form panel, passes on all info to the doPost(e) (no handler needed on the
    submit button).