【www.bbyears.com--php函数】
cookie是记录访客足迹及留住访客的良好手段之一,但是处理cookie还是挺麻烦的,下面小指分享三个处理cookie的协助函数,你可以保存在类似cookie.js的文件里,然后调用即可使用这三个神奇的函数了。
首先了解一下cookie的结构:cookie是以键值对的形式保存的,即key=value的格式,各个cookie之间一般是以“;”分隔。
writeCookie(name,value,days):写入cookie
name为cookie键名,value为cookie键值,days为天数,可选,不输入则cookie在网页结束后就失效了。
readCookie(name):读取cookie
name为cookie键名,返回cookie键值
eraseCookie(name):清除cookie
name为cookie键名,清除方法为设为空值并有效期为过去-1天。
function writeCookie(name, value, days) {
// By default, there is no expiration so the cookie is temporary
var expires = "";
// Specifying a number of days makes the cookie persistent
if (days) {
var date = new Date();
date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
expires = "; expires=" + date.toGMTString();
}
// Set the cookie to the name, value, and expiration date
document.cookie = name + "=" + value + expires + "; path=/";
}
function readCookie(name) {
// Find the specified cookie and return its value
var searchName = name + "=";
var cookies = document.cookie.split(";");
for(var i=0; i < cookies.length; i++) {
var c = cookies[i];
while (c.charAt(0) == " ")
c = c.substring(1, c.length);
if (c.indexOf(searchName) == 0)
return c.substring(searchName.length, c.length);
}
return null;
}
function eraseCookie(name) {
// Erase the specified cookie
writeCookie(name, "", -1);
}
另外最好在使用cookie的使用采用if (navigator.cookieEnabled)检测客户端是否支持cookie。