change checked checkbox in jquery code example
Example 1: jquery set checkbox checked
//jQuery 1.6+ use
$('.checkbox').prop('checked', true);
//jQuery 1.5.x and below use
$('.checkbox').attr('checked', true);
Example 2: jquery set checkbox checked
<script>
//jQuery 1.6+ use
$('#checkbox').prop('checked', true);
//jQuery 1.5.x and below use
$('#checkbox').attr('checked', true);
</script>