~小随笔~ Cookie AND 本地存储

Cookie

cookie 用于存储web页面的用户信息

cookie 存储大小为4K 可以设置过期时间，如果不设置关闭浏览器窗口自动删除

添加cookie方法

function setCookie(key,value,expires) {
    var date = new Date();
    date.setDate(date.getDate() +expires*1);
    document.cookie = key+'='+value+';expires='+date.toUTCString()
} 

删除cookie

function deleteCookie(key){
    var date = new Date();
    date.setDate(date.getDate() -1);
    document.cookie = key + '=null;expires=' +date.toUTCString();
}

获取cookie

function getCookie(key){
    var tmp = document.cookie;
    tmp = tmp.split(';')
    //tmp = 'name=...; text=...'
    //["name=..."," text=111"]
    for(var i=0;i<tmp.length;i++){
        //['name','...']
        var arr = tmp[i].split('=')
        // console.log(arr);
        //如果key与输入值相等 输出值
        if(arr[0].trim()== key){
            return arr[1];
        }
    }
}

本地存储

本地存储方式

1. localStorage:返回值为对象 可存数据大小5M 会永久的存储在浏览器中 除非手动删除

2. sessionStorage返回值为对象 可存数据大小5M 浏览器窗口关闭自动删除

设置localStorage

//法1.localStorage 
localStorage.name = 'John';
//法2.localStorage.setItem(key,value)
localStorage.setItem('age',18); 

获取localStorage

//1.localStorage.key;
 console.log(localStorage.name);//John
 //2.localStoorage.getItem(key);
 localStorage.setItem('age',18); //18

设置localStorage

sessionStorage.weight = '60kg';
sessionStorage.setItem('height','170cm')

获取localStorage

console.log(sessionStorage.weight);//60kg
console.log(sessionStorage.getItem('height'));//170cm