/*
版主推荐滚动
*/
(function($){
$.fn.extend({
        scroll:function(opt,callback){
                //参数初始化
                if(!opt) var opt={};
                var _btnup = $("#"+ opt.up);//shawphy:向上按钮
                var _btndown = $("#"+ opt.down);//shawphy:向下按钮
                var timerid;
                var _this=this.eq(0).find("ul:first");
                var     lineh=_this.find("li:first").height(), //获取行高
                        line=opt.line?parseint(opt.line,10):parseint(this.height()/lineh,10), //每次滚动的行数，默认为一屏，即父容器高度
                        speed=opt.speed?parseint(opt.speed,10):500; //卷动速度，数值越大，速度越慢（毫秒）
                        timer=opt.timer //?parseint(opt.timer,10):3000; //滚动的时间间隔（毫秒）
                if(line==0) line=1;
                var upheight=0-line*lineh;
                //滚动函数
                var scrollup=function(){
                        _btnup.unbind("click",scrollup); //shawphy:取消向上按钮的函数绑定
                        _this.animate({
                                margintop:upheight
                        },speed,function(){
                                for(i=1;i<=line;i++){
                                        _this.find("li:first").appendto(_this);
                                }
                                _this.css({margintop:0});
                                _btnup.bind("click",scrollup); //shawphy:绑定向上按钮的点击事件
                        });

                }
                //shawphy:向下翻页函数
                var scrolldown=function(){
                        _btndown.unbind("click",scrolldown);
                        for(i=1;i<=line;i++){
                                _this.find("li:last").show().prependto(_this);
                        }
                        _this.css({margintop:upheight});
                        _this.animate({
                                margintop:0
                        },speed,function(){
                                _btndown.bind("click",scrolldown);
                        });
                }
               //shawphy:自动播放
                var autoplay = function(){
                        if(timer)timerid = window.setinterval(scrollup,timer);
                };
                var autostop = function(){
                        if(timer)window.clearinterval(timerid);
                };
                 //鼠标事件绑定
                _this.hover(autostop,autoplay).mouseout();
                _btnup.css("cursor","pointer").click( scrollup ).hover(autostop,autoplay);//shawphy:向上向下鼠标事件绑定
                _btndown.css("cursor","pointer").click( scrolldown ).hover(autostop,autoplay);

        }       
})
})(jquery);






//<script type="text/javascript">
$(document).ready(function(){
        $("#scrolldiv").scroll({line:1,speed:500,timer:3000,up:"but_up",down:"but_down"});
});