JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8/themes/dot-luv/jquery-ui.css">
<div class="portlet-header">
    Company Information ... <button> some button here </button>
</div>
<div class="portlet-content">
    <div class="content_regular">
        <table style=" width:100%; height:100%;">
            <tr><td>...content</td></tr>
        </table>
    </div>
</div>

JavaScript

$('.portlet-header button').click(function(){
   alert($('.content_regular').html())
});