JSFiddle - React, Tailwind, and code Playground
HTML
<input type="checkbox" class="friend" id="abbsmalone_select" />
<input type="checkbox" class="friend" id="cchkorea_select" />
<br/>
<input id="deselect_all" type="button" class="form_button2" value="deselect all" style="float: left;">
<input id="select_all" type="button" class="form_button2" value="select all" style="float: left;">
JavaScript
function selectAll() {
jQuery(".friend").prop('checked', true);
}
function deselectAll() {
jQuery(".friend").prop('checked', false);
}
jQuery(function() {
jQuery("#deselect_all").click(deselectAll);
jQuery("#select_all").click(selectAll);
});