function timertab(t,to,c,co,s,a,tim){
this.obj = document.getElementById(t).getElementsByTagName(to);//导航对象
this.eles = document.getElementById(c).getElementsByTagName(co);//内容项
this.start = s-1;//初始项目
this.speed = tim;//切换间隔
this.setid = null;//定时器
var loop = function(){ //自动切换
for(var i=0,j=obj.length;i<j;i++){//初始化
obj[i].className = "";
eles[i].className = "";
}
obj[start].className = "on";//当前项
eles[start].className = "on";
setid=setTimeout(loop,speed);//开始自动切换
start++;
if(start==obj.length){
start=0;
}
};loop();
var clik = function(){ //点击
for(var i=0;i<obj.length;i++){
obj[i].onclick = function(){
clearTimeout(setid);//停止原来的自动切换
var inb = this.id.substr(this.id.indexOf("#")+a,1);//原为为A标签herf属性，改为取ID
for(var i=0,j=obj.length;i<j;i++){
obj[i].className = "";
eles[i].className = "";
} 
this.className = "on";
eles[inb-1].className = "on";
/*从点击项开始自动切换，此功能可以选择去掉*/
start=inb-1;
loop();
} 
} 
};clik(); 
var m_over = function(){//鼠标指向暂停自动切换 
for(var i=0;i<obj.length;i++){ 
eles[i].onmouseover = function(){clearTimeout(setid)};
}
};m_over();
var m_out = function(){//鼠标离开继续自动切换
for(var i=0;i<obj.length;i++){
eles[i].onmouseout = function(){setid=setTimeout(loop,speed)};
}
};m_out();
}