Processing Dynamic Form

Question

I've a JS dynamic form, where i can add or remove fields:

Field 1
Field 2
Field 3
Field 4

Now if I remove Field 2 and add a new field:

Field 1
Field 3
Field 4
Field 5

I'm sending this through Ajax POST inside a form element. My problem is server side PHP processing. How can I know how many fields I have inside $_POST array and what are their ids? I'm generating unique id using "field" + counterIndex, but following the example how can I be able to understand that I have a total of 4 fields and that number 2 is missing? By the way, inside the form I have static fields too.

Answer 1

This can be done through PHP as $_POST is itself an array thus it can be looped.

Say, you have fields :

<input name="dyn[id1]"/>

<input name="dyn[id2]"/>

In the backend PHP file,

Loop through the $_POST as following:

<?php
if (isset($_POST['SUBMIT_BTN'])) {
  if (! empty($_POST['dyn'])) {
    foreach ($_POST['dyn'] as $dyn_id => $dyn_val) {
     // "$dyn_id" is your ID you needed.
    }
  }
}
?>