JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://github.com/douglascrockford/JSON-js/raw/8e0b15cb492f63067a88ad786e4d5fc0fa89a241/json2.js"></script>
<form id="form1">
    <input id="code" type="text" name="code" />
    <input id="name" type ="text" name="name" />
    <input type="submit" id="submit" />
</form>

JavaScript

$(function() {

    $('#submit').click(function(evt) {

        //Stop submit button from posting form (default behaviour)
        evt.preventDefault();

        //Create a javascript object literal
        var p = {
            Name: $('#name').val(),
            Code: $('#code').val()
        };

        /*
        JSON.stringify built in function to IE9+ / FireFox / Chrome browsers that
        converts JavaScript Object Literals into JSON.  Include JSON2.js for all others found at 
        https://github.com/douglascrockford/JSON-js/blob/master/json2.js

        I prefer using stringify as it reduces the need to manually construct JSON 
        however for this simple example you could do this
        
        Replace "json" : JSON.stringify(p) with
            { "Name" : $('#name').val(), "Code" : $('#code').val() }
        */

        // Replace echo/json with url of php class 
        $.post('/echo/json/', {
            "json": JSON.stringify(p)
        }, function(result) {
            //Result from Server
            alert(result.Name);
        });

        // Server Side
        // <?php echo $_POST["Name"]; ?>
        // <?php echo $_POST["Code"]; ?>
    });

});