Answers for "jquery check if element exists in div"

jQuery exists function

if ($("#myElementID").length){
   //I exist
}

jquery check if element still exists

$(function() {
    var $button = $(".the_button");
    alert (isStale($button));
    $button.remove();
    alert (isStale($button));
});
    
function isStale($elem)
{
    return $elem.closest("body").length > 0;
};