setinterval 用法

<script>var ad_bimg_index = 1;var ad_bimg_timeid;var intout ;
$(document).ready(function(){ intout = window.setInterval("big_img()",3000);});

function big_img(){ var num = $('div[id^=con_six_]').length; setTab('six',ad_bimg_index,num); ad_bimg_index++; if(ad_bimg_index>num) { ad_bimg_index = 1; }}
function bimg_act(i,a) { ad_bimg_index = i; if(a==1) { intout = window.clearInterval(intout); } else { intout = window.setInterval("big_img()",5000); }}
function setTab(name,cursel,n){ for(i=1;i<=n;i++){ var menu=document.getElementById(name+i); if(menu == null || menu == 'undefined'){ }else{ var con=document.getElementById("con_"+name+"_"+i); menu.className=i==cursel?"hover":""; con.style.display=i==cursel?"block":"none"; } }}</script>本文出自 “Smile” 博客，请务必保留此出处http://nightwizard.blog.51cto.com/2181643/565787