I found a method that sender.get_commandArgument() can get the stored value in e.commandArguement. Then use split to get the targeted message.

    function UnlockConfirm(sender, args) {
            var commandArgument = sender.get_commandArgument();
            var parts = commandArgument.split('|');
            var recordNo = parts[2];

            if (No != "") {
                args.set_cancel(!confirm('Confirm to delete record' + No + '?'));     
            } else {
                args.set_cancel(!confirm('Confirm to delete?'));
            }
        }