JSFiddle - React, Tailwind, and code Playground
HTML
<div id="checkboxes">
<input id="chkbx_0" type="checkbox" name="c0" checked="checked" />Option 1
<input id="chkbx_1" type="checkbox" name="1" />Option 2
<input id="chkbx_2" type="checkbox" name="2" />Option 3
<input id="chkbx_3" type="checkbox" name="3" checked="checked" />Option 4
</div>
<input type="button" id="clickme" value="click me, now!" />
JavaScript
$("#clickme").click(function(e){
var selected = $("#checkboxes input:checked").map(function(i,el){return el.name;}).get();
alert("selected = [" + selected + "]\nas string = \"" + selected.join(";") + "\"");
});