cookie幾大作用:
1.保持使用者登陸狀态
2.跟蹤使用者行為
3.制定頁面
4.建立購物車
cookie缺點:
1. 可能被禁用
2.可能被删除:cookie是一個檔案,容易被使用者删除
3.安全性不高
4.cookie可能與浏覽器相關
設定cookie
document.cookie = "userId = 100";
alert(document.cookie);
設定多個值:
document.cookie ="userId = 100;userPass = 23256";
由于在設定多個Cookie時,它擷取的是全部的cookie。而不能擷取指定cookie的名稱的值,是以用下面的代碼實作:
Document.cookie=“userld = 100”;
Document.cookie = “passWord = 123456”;
Var strCookie = document.cookie;
Var arrCookie = strCookie.split(‘;’);
Var userId;
For(var I = 0; i< arrCookie.length; i++) {
Var arr = arrCookie.split(‘=‘);
If(‘userId’ == arr[0]) {
userId = arr[1];
Break;
}
Alert(userId);
Cookie設定終止日期
var date = new Date();
var stopDays = 0.1;
date.setTime(date.getTime() + stopDays*24*3600*1000);
document.cookie = "userId = 100;userName = 123456;stop = "+date.toGMTString();
alert(document.cookie);
删除Cookie: 主要是在設定終止日期的基礎上減去一個時間就行了
// function deleteCookie(name) {
// var date = new Date();
// date.setTime(date.getTime() - 100000);
// document.cookie = name + "= afd; expires = " + date.toGMTString();
// return document.cookie;
// }
// alert(deleteCookie("chen"));
設定Cookie的通路路徑
Document.cookie = “userId = 100; path = /one”;
表示隻能在one目錄下使用
使用domain = 參數設定cookie的通路主機名
Document.cookie = “ userId = 100; domain = .google.com”;
這表示所有的google.com下的所有主機都可以通路Cookie
添加cookie的通用函數
Function addCookie(name, value, expiresHours) {
Var cookieString = name + “=” + escape(value);
If(expiresHours > 0) {
Var date = new Date();
Date.setTime(date.getTime() + expirsHours * 3600 * 1000);
cookieString = cookieString +”; expires = “ + date.toGMTString();
Document.cookie = cookieString;
Return document.cookie;
指定Cookie值:getCookie(name)
function getCookie(name) {
var strCookie = document.cookie;
var arrCookie = strCookie.split(";");
for (var i = 0; i < arrCookie.length; i++) {
var arr = arrCookie[i].split("=");
if (arr[0] == name) {
return arr[1];
};
};
return arr[1];
删除Cookie:deleteCookie(name)
function deleteCookie(name) {
var date = new Date();
date.setTime(date.getTime() - 100000);
document.cookie = name + "= afd; expires = " + date.toGMTString();
return document.cookie;