基于jquery的无缝循环新闻列表插件

(function($){
$.fn.extend({
newsList:function(options){
var defaults ={
actName:'li', //显示条数名；
maxShowNum:'6', //最多的显示条数；
actNameH:'28', //一次移动的距离；
ulClass:'.ul_news_list', //被复制层的class
copyUlClass:'.ul_news_list2', //复制层的class
autoTime:'1500', //自动运行时间；
clickGoUpC:'.go_uplist', //点击向上class;
clickDownUpC:'.go_downlist', //点击向下class;
goStart:'go_tart',
autoCloss:'flase' //自动运行开关,当为'flase'时为开，其它则关；
} ;

options = $.extend(defaults, options);
return this.each(function(){
var o = options;
var counts =1;
var linum = $($(this).find(o.actName),$(this)).size();
var ul_class = $($(this).find(o.ulClass),$(this));
var copy_ul_class = $($(this).find(o.copyUlClass),$(this));
var click_go_up_c = $($(this).find(o.clickGoUpC),$(this));
var click_go_down_C = $($(this).find(o.clickDownUpC),$(this));
var go_start = $($(this).find(o.goStart),$(this));
if(linum > o.maxShowNum){
$(copy_ul_class).html($(ul_class).html());
goStartList();
}
var thiswrap = $($(ul_class).parent().parent(),$(this));
//自动运行函数
function auto_function(){
if(counts <= linum){
$(ul_class).animate({top:'-=' + o.actNameH},o.autoTime);
$(copy_ul_class).animate({top:'-=' + o.actNameH},o.autoTime);
counts++;
}else{
$(ul_class).animate({top:0},0);
$(copy_ul_class).animate({top:0},0);
counts = 1;
}
}
//点击向上移动时；
if(linum > o.maxShowNum){
$(click_go_up_c).click(function(){
if(counts <= linum){
$(ul_class).animate({top:'-=' + o.actNameH},0);
$(copy_ul_class).animate({top:'-=' + o.actNameH},0);
counts++;
}else{
$(ul_class).animate({top:0},0);
$(copy_ul_class).animate({top:0},0);
counts = 1;
}
});
}
//点击向下移动时；
if(linum > o.maxShowNum){
$(click_go_down_C).click(function(){
if(counts > 1){
counts--;
$(ul_class).animate({top:'-'+ counts*o.actNameH},0);
$(copy_ul_class).animate({top:'-'+ counts*o.actNameH},0);
}else{
$(ul_class).animate({top:0},0);
$(copy_ul_class).animate({top:0},0);
counts = linum+1;
}
});
}
//鼠标经过所发生的开始停止；
if(linum > o.maxShowNum){
$(thiswrap).hover(function(){
goStopList();
},function(){
goStartList();
});
}
function goStartList(){
if(o.autoCloss === 'flase'){
go_start = setInterval(auto_function,o.autoTime);
}
}
function goStopList(){
clearInterval(go_start);
}
});
}
});
}(jQuery));

<script language="javascript">
$(document).ready(function(){
$("#newslist").newsList();
});
</script>

<div id="newslist">
<div class="go_upanddown"><span class="go_uplist"><img src="images/newslist/goupbtn.gif" /></span><span class="go_downlist"><img src="images/newslist/godownbtn.gif" /></span></div>
<div class="news_list_bar">
<ul class="ul_news_list">
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<li><a href="#">8、湖北武汉汉曾参加过唐曾参加过唐曾参加过唐曾参加过唐集在江边观</a></li>
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</ul>
<ul class="ul_news_list2"></ul>
</div>
</div>

body { font-family:"微软雅黑",Arial,"Lucida Grande", Verdana, Lucida; font-size:12px; }
*{ padding:0; margin:0;}
img { border:0;}
.clear { clear:both;}
a { color:#000; text-decoration:none;}
a:hover { color:#EC6104; text-decoration:none;}
.undis { display:none;}/*news_list*/
.news_list_bar { position:relative; width:560px; height:168px; overflow:hidden; background:url(../images/slideshow2/v3_picture6.gif) repeat-y; background-color:#F00;}
.ul_news_list,
.ul_news_list2{ position:relative; list-style:none;}
.ul_news_list li,
.ul_news_list2 li{line-height:28px; height:28px; width:500px; overflow:hidden; white-space:nowrap;padding:0 20px;}
.ul_news_list li a,
.ul_news_list2 li a{ padding-right:20px;}
.go_upanddown { position:absolute; margin:-20px 0 0 500px;}
.go_upanddown span { padding-right:10px; cursor:pointer;}