jquery check / uncheck checkbox

<input type="checkbox" name="all" id="checkall" />

$('#checkall:checkbox').change(function () {
   if($(this).attr("checked")) $('input:checkbox').attr('checked','checked');
   else $('input:checkbox').removeAttr('checked');
});

kalau memakai class

<input type="checkbox" name="all" id="checkall" />
<input type="checkbox" name="cando" class="pCheck" />
<input type="checkbox" name="canclose" class="pCheck" />
<input type="checkbox" name="canassign" class="pCheck" />

$('#checkall:checkbox').change(function () {
   if($(this).attr("checked")) $('input:checkbox[class=pCheck]').attr('checked','checked');
   else $('input:checkbox[class=pCheck]').removeAttr('checked');
});

menggunakan fungsi toggle (biasanya digunakan untuk button/ link, kalau pakai checkbox -centang nya ga muncul

$(document).ready(function(){
    $('.check:button').toggle(function(){
        $('input:checkbox').attr('checked','checked');
        $(this).val('uncheck all');
    },function(){
        $('input:checkbox').removeAttr('checked');
        $(this).val('check all');        
    })
})