function selectAll() {
$("#DivContainingCheckboxesID :checkbox").attr('checked', true);
}
function selectNone() {
$("#DivContainingCheckboxesID :checkbox").attr('checked', false);
}
//if you want to do something specific for each check box
$("#DivContainingCheckboxesID :checkbox").each(function () {
//do it here
if (this.checked)
this.click();});