in PHP
<?php
header('Content-Type: application/json');
echo json_encode(array('test' => html_entity_decode("Hello – World", ENT_COMPAT, 'UTF-8')));
:
{"test":"Hello \u2013 World"}
JS:
var o = jQuery.parseJSON('{"test":"Hello \u2013 World"}');
alert( o.test );
:
Hello – World