Is it possible adding a button with PHP, which could be used for adding an optional text input field by client side user? My purpose is actually very simple: The client side users could be free creating and adding more and customized variables, which are intended to be used as strings and related or associated variables.
So, am I able to do these kind of tasks simply using PHP alone? Or, should I use some JavaScript like technologies to make those functions available in real world’s practices?
You have two options: have JavaScript add the extra fields to the HTML and then process them in PHP when the form is submitted or submit the form every time you want to add a field then process the result with one final submit. I would say the easiest way would be using JavaScript. Post back if you need some help implementing one of the above.