jquery全选与反选插件怎么写？实例代码

$(function () {  
    //调用全选插件 
    $.fn.check({ checkall_name: "checkall", checkbox_name: "check" }) 
}); 
//全选插件 www.jb200.com
//checkall_name   操作全选的复选框name 
//checkbox_name   被操作的复选框的name  name值可不统一 设置包含值 以XXX开头 自己修改 
(function ($) { 
    $.fn.check = function (options) { 
        var defaults = { 
            checkall_name: "checkall_name", //全选框name 
            checkbox_name: "checkbox_name" //被操作的复选框name 
        }, 
        ops = $.extend(defaults, options); 
        e = $("input[name='" + ops.checkall_name + "']"), //全选 
        f = $("input[name='" + ops.checkbox_name + "']"), //单选 
        g = f.length; //被操作的复选框数量 
        f.click(function () { 
            $("input[name ='" + ops.checkbox_name + "']:checked").length == $("input[name='" + ops.checkbox_name + "']").length ? e.attr("checked", !0) : e.attr("checked", !1); 
        }), e.click(function () { 
            for (i = 0; g > i; i++) f[i].checked = this.checked; 
        }); 
    }; 
})(jQuery);