这是一个代码获取，设置和删除Cookie在JavaScript。

function getCookie(name) { name = name + "="; var cookies = document.cookie.split(';'); for(var i = 0; i <cookies.length; i++) { var cookie = cookies[i]; while (cookie.charAt(0)==' ') { cookie = cookie.substring(1); } if (cookie.indexOf(name) == 0) { return cookie.substring(name.length,cookie.length); } } return ""; } function setCookie(name, value, expirydays) { var d = new Date(); d.setTime(d.getTime() + (expirydays*24*60*60*1000)); var expires = "expires="+ d.toUTCString(); document.cookie = name + "=" + value + "; " + expires; } function deleteCookie(name){ setCookie(name,"",-1); }

来源:http://mycodingtricks.com/snippets/javascript/javascript-cookies/

一种厚脸皮的、简单的读取cookie的方法可能是这样的:

let username, id; 
eval(document.cookie); 
console.log(username + ", " + id); // John Doe, 123

如果您知道您的cookie包含以下内容，则可以使用此方法:用户名="John Doe";id = 123;。注意，字符串在cookie中需要引号。可能不是推荐的方法，但对测试/学习有效。

以下是可以用于创建和检索cookie的函数。

function createCookie(name, value, days) {
    var expires;
    if (days) {
        var date = new Date();
        date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
        expires = "; expires=" + date.toGMTString();
    }
    else {
        expires = "";
    }
    document.cookie = name + "=" + value + expires + "; path=/";
}

function getCookie(c_name) {
    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 "";
}

在ES6中读取cookie的简单方法。

function getCookies() {
    var cookies = {};
    for (let cookie of document.cookie.split('; ')) {
        let [name, value] = cookie.split("=");
        cookies[name] = decodeURIComponent(value);
    }
    console.dir(cookies);
}

下面是前面提到的w3schools的例子。

function setCookie(cname, cvalue, exdays) {
    var d = new Date();
    d.setTime(d.getTime() + (exdays*24*60*60*1000));
    var expires = "expires="+ d.toUTCString();
    document.cookie = cname + "=" + cvalue + ";" + expires + ";path=/";
}

function getCookie(cname) {
    var name = cname + "=";
    var decodedCookie = decodeURIComponent(document.cookie);
    var ca = decodedCookie.split(';');
    for(var i = 0; i <ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0) == ' ') {
            c = c.substring(1);
        }
        if (c.indexOf(name) == 0) {
            return c.substring(name.length, c.length);
        }
    }
    return "";
}

chrome团队提出了一种新的方式管理Cookie与Cookie存储API异步(可在谷歌chrome从版本87开始):https://wicg.github.io/cookie-store/

今天已经在其他浏览器中使用了它:https://github.com/mkay581/cookie-store

// load polyfill
import 'cookie-store';

// set a cookie
await cookieStore.set('name', 'value');
// get a cookie
const savedValue = await cookieStore.get('name');