Question

I want to send the properties of HTML elements as data via POST, for example whether an element is visible or not?

Answer 1

You cannot do it with PHP and HTML alone, since the HTML form would only post a form input’s name. You would need to add some JavaScript, which at the time the form is submitted, would iterate over all its inputs and modify their values to include the attribute values as well.

Example:

yourform.onbeforesubmit = function() {
  // Loop over form elements and append -visible or -hidden to its value based on CSS style
  // jQuery selectors like .is(":visisble") would help a lot here.
  // This is just a basic example though - it would require an explicit visibility CSS rule on each 
  // input element...
  for (var i=0; i<yourform.elements.length; i++) {
    yourform.elements[i].value = += "-" + yourform.elements[i].style.visibility;
  }
}

Another method would be rather than to modify the values of the inputs themselves, keep a hidden input for each visible user input and set the attributes as the value to the hidden input rather than the visible input.