日期:2014-05-16  浏览次数:20346 次

javascript 处理cookie
这里展示了cookie的存 取 和删除
其实删除和存的原理是一样  只是有效期设置为过去的时间


<html>
<head>
<script type="text/javascript">

function getCookie(c_name) //取cookie
{
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) //存cookie
{
var exdate=new Date()
exdate.setDate(exdate.getDate()+expiredays)
document.cookie=c_name+ "=" +escape(value)+
((expiredays==null) ? "" : "; expires="+exdate.toGMTString())
}

function checkCookie()      //检查cookie
{
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)
    }
  }
function delCookie(name)//删除cookie
{
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval=getCookie(name);
    if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString();
} 
}
</script>
</head>
<body onLoad="checkCookie()">
</body>
</html>