js读写(删除)Cookie实例详解

//JS操作cookies方法! 
//写cookies 
function setCookie(name,value) 
{ 
var Days = 30; 
var exp = new Date(); 
exp.setTime(exp.getTime() + Days*24*60*60*1000); 
document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString(); 
} 
//读取cookies 
function getCookie(name) 
{ 
var arr,reg=new RegExp("(^| )"+name+"=([^;]*)(;|$)"); 
if(arr=document.cookie.match(reg)) return unescape(arr[2]); 
else return null; 
} 
//删除cookies 
function delCookie(name) 
{ 
var exp = new Date(); 
exp.setTime(exp.getTime() - 1); 
var cval=getCookie(name); 
if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString(); 
} 
//使用示例 
setCookie("name","hayden"); 
alert(getCookie("name")); 
//如果需要设定自定义过期时间 
//那么把上面的setCookie　函数换成下面两个函数就ok; 
//程序代码 
function setCookie2(name,value,time){ 
var strsec = getsec(time); 
var exp = new Date(); 
exp.setTime(exp.getTime() + strsec*1); 
document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString(); 
} 
function getsec(str){ 
alert(str); 
var str1=str.substring(1,str.length)*1; 
var str2=str.substring(0,1); 
if (str2=="s"){ 
return str1*1000; 
}else if (str2=="h"){ 
return str1*60*60*1000; 
}else if (str2=="d"){ 
return str1*24*60*60*1000; 
} 
} 
//这是有设定过期时间的使用示例： 
//s20是代表20秒 
//h是指小时，如12小时则是：h12 
//d是天数，30天则：d30 
//暂时只写了这三种 
setCookie2("name2","hayden2","s20"); 
alert(getCookie("name2"));

以下是几个比较常见的好用的函数：

function GetCookieVal(offset) 
//获得Cookie解码后的值 
{ 
var endstr = document.cookie.indexOf (";", offset); 
if (endstr == -1) 
endstr = document.cookie.length; 
return unescape(document.cookie.substring(offset, endstr)); 
} 
function SetCookie(name, value) 
//设定Cookie值 
{ 
var expdate = new Date(); 
var argv = SetCookie.arguments; 
var argc = SetCookie.arguments.length; 
var expires = (argc > 2) ? argv[2] : null; 
var path = (argc > 3) ? argv[3] : null; 
var domain = (argc > 4) ? argv[4] : null; 
var secure = (argc > 5) ? argv[5] : false; 
if(expires!=null) expdate.setTime(expdate.getTime() + ( expires * 1000 )); 
document.cookie = name + "=" + escape (value) +((expires == null) ? "" : ("; expires="+ expdate.toGMTString())) 
+((path == null) ? "" : ("; path=" + path)) +((domain == null) ? "" : ("; domain=" + domain)) 
+((secure == true) ? "; secure" : ""); 
} 
function DelCookie(name) 
//删除Cookie 
{ 
var exp = new Date(); 
exp.setTime (exp.getTime() - 1); 
var cval = GetCookie (name); 
document.cookie = name + "=" + cval + "; expires="+ exp.toGMTString(); 
} 
function GetCookie(name) 
//获得Cookie的原始值 
{ 
var arg = name + "="; 
var alen = arg.length; 
var clen = document.cookie.length; 
var i = 0; 
while (i < clen) 
{ 
var j = i + alen; 
if (document.cookie.substring(i, j) == arg) 
return GetCookieVal (j); 
i = document.cookie.indexOf(" ", i) + 1; 
if (i == 0) break; 
} 
return null; 
} 
//测试 
SetCookie("sunshine","1986"); 
alert(GetCookie("sunshine"));