I am trying to select all checkboxes on a page once the 'select all' checkbox is clicked and i am using jquery for this as you can see at the below link:

http://jsfiddle.net/priyam/K9P8A/

The code to select and unselect all checkbox is:

function selectAll() {

    $('.selectedId').attr('checked', isChecked('selectall'));

}



function isChecked(checkboxId) {

    var id = '#' + checkboxId;

    return $(id).is(:checked);

}

After being stuck with it for a day, I am still not sure why I cant get it to work. Please help