Jquery实用代码片段（转）

1、把所有带有#的空链接换成不友情的链接

    $('a[href="#"]').each(function() {   
        $(this).attr('href', 'javascript:void(0)')   
    });  

2、jQuery全选与取消全选插件

(function($){   
    $.fn.checkall = function(options){   
        var defaults = {chname:"checkname[]", callback:null},   
            options = $.extend(defaults, options),   
            $obj = $(this),   
            $items = $("input[name='"+options.chname+"']"),   
            checkedItem = 0;   
        $items.click(function(){   
            if($items.filter(":checked").length === $items.length){   
                $obj.attr("checked",true);   
            }else{   
                $obj.removeAttr("checked");   
            }   
            checkedItem = $items.filter(":checked").length;   
            if(typeof options.callback === "function") options.callback(checkedItem);   
        });   
        return $obj.each(function(){   
            $(this).click(function(){   
                if($(this).attr("checked")){   
                    $items.attr("checked",true);   
                }else{   
                    $items.removeAttr("checked");   
                }   
                checkedItem = $items.filter(":checked").length;   
                if(typeof options.callback === "function") options.callback(checkedItem);   
            });   
        });   
    }   
})(jQuery);

JS