来研究一下yahoo的酷图幻灯js代码

　　http://cn.sports.yahoo.com/040109/262/1ypby.Html

js代码如下：

var PUisIE_NAV4 = false;

if (parseFloat(navigator.appVersion) >= 4) {

PUisIE_NAV4 = true;

}

var PUwinWidth='740';

var PUwinHeight='320';

var PUtimes = 1; /* number of times to show ad. if > times, then redirect thru */

//var PUtheDomain = ".cn.yahoo.com";

var PUtheDomain = document.domain;

var PUeXPiresIn = 4/24; /* days between shows of the ad */

function errorsuppressor(){

return true

}

window.onerror=errorsuppressor;

function PUsetCook(t,expIn) {

var cook;

var PUexDate;

PUexDate = new Date;

PUexDate.setTime(PUexDate.getTime() + expIn*24*60*60*1000);

cook = "PU=t="+t+"; expires=" + PUexDate.toGMTString() +"; domain="+PUtheDomain + "; path=/";

document.cookie = cook;

}

var PU_NO_COOKIES = 9999;

function PUgetCook(x) {

var i,j,a,b,s,e,d,f;

a = document.cookie;

if (a == "") return PU_NO_COOKIES;

s = a.indexOf(x + "=");

if (s == -1) return false;

s += x.length+1;

e = a.indexOf(';',s);

if (e == -1) e = a.length;

return a.substring(s,e);

}

/* check cookies - if cookies are off or if user saw it X times, then we redirect thru */

var PUd;

var PUb=PUgetCook("PU");

var PUoverTimes = 0;

if (PUb == PU_NO_COOKIES) {

PUoverTimes = 1;

} else {

if (PUb != false) {

PUb = PUb.split('&');

for (PUi=0; PUi

PUd = PUb[PUi].split('=');

if (PUd == "t") {

last;

}

}

PUd[1]++;

if (PUd[1] > PUtimes) {

PUoverTimes = 1;

} else {

PUsetCook(PUd[1],PUexpiresIn);

}

} else {

PUsetCook(1,PUexpiresIn);

}

}

function PUlaunchPU(){

var PUwin;

var addIt = PUisIE_NAV4 ? ',top=5000,left=5000' : '';

PUwin=window.open('about:blank','PUwin', 'width='+PUwinWidth+',height='+PUwinHeight+',location=no,menubar=no,titlebar=no,status=no,toolbar=no,scrollbars=yes,resizable=no'+addIt,true);

PUwin.blur();

return PUwin;

}

//if ((PUoverTimes < 1)&&(navigator.userAgent.indexOf("Unix")==-1)) {

document.write('