JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
<li class="dropped" data-order="0" data-id="1" data-content="blabla">first</li>
<li class="dropped" data-order="0" data-id="2" data-content="another content">second</li>
</ul>

<div id="result"></div>

<button class="send">Send</button>

JavaScript

$(".send").click(function() {

    var itterate = $(".dropped");
    var data_array = new Array();
    $(".dropped").each(function(){
        
        var item = {};
        item['data-order'] = $(this).data('order');
        item['data-id'] = $(this).data('id');
        item['data-content'] = $(this).data('content');

        data_array.push(item);

    });
    var serialized = JSON.stringify(data_array);

    $("#result").text(serialized);

});