记录访客的欢迎cookie

<html>
<head>
<script type=”text/javascript”>
function getCookie(c_name)
{
if (document.cookie.length>0)
{
c_start=document.cookie.indexOf(c_name + “=”)
if (c_start!=-1)
{
c_start=c_start + c_name.length+1
c_end=document.cookie.indexOf(“;”,c_start)
if (c_end==-1) c_end=document.cookie.length
return unescape(document.cookie.substring(c_start,c_end))
}
}
return “”
}

function setCookie(c_name,value,expiredays)
{
var exdate=new Date()
exdate.setDate(exdate.getDate()+expiredays)
document.cookie=c_name+ “=” +escape(value)+
((expiredays==null) ? “” : “; expires=”+exdate.toGMTString())
}

function checkCookie()
{
username=getCookie(\’username\’)
if (username!=null && username!=””)
{alert(\’Welcome again \’+username+\’!\’)}
else
{
username=prompt(\’Please enter your name:\’,””)
if (username!=null && username!=””)
    {
    setCookie(\’username\’,username,365)
    }
}
}
</script>
</head>
<body onLoad=”checkCookie()”>
</body>
</html>