如何在JavaScript中创建和读取cookie的值?


当前回答

readCookie的改进版本:

function readCookie( name )
{
    var cookieParts = document.cookie.split( ';' )
    ,   i           = 0
    ,   part
    ,   part_data
    ,   value
    ;

    while( part = cookieParts[ i++ ] )
    {
        part_data = part.split( '=' );

        if ( part_data.shift().replace(/\s/, '' ) === name )
        {
            value = part_data.shift();
            break;
        }

    }
    return value;
}

一旦你找到你的cookie值并返回它的值,它就会被打破。在我看来,双劈非常优雅。

if条件上的替换是一个空白修饰,以确保它正确匹配

其他回答

通过类似sessionStorage和localStorage的接口:

const cookieStorage = {
  getItem: (key) {
    const cookies = document.cookie.split(';')
      .map(cookie => cookie.split('='))
      .reduce(
        (accumulation, [key, value]) => ({...accumulation, [key.trim()]: value}),
        {}
      )
    
    return cookies[key]
  },
  setItem: (key, value) {
    document.cookie = `${key}=${value}`
  },
}

它的用法cookieStorage。setItem(", ")和cookieStorage.getItem(")。

简约且功能齐全的ES6方法:

const setCookie = (name, value, days = 7, path = '/') => {
  const expires = new Date(Date.now() + days * 864e5).toUTCString()
  document.cookie = name + '=' + encodeURIComponent(value) + '; expires=' + expires + '; path=' + path
}

const getCookie = (name) => {
  return document.cookie.split('; ').reduce((r, v) => {
    const parts = v.split('=')
    return parts[0] === name ? decodeURIComponent(parts[1]) : r
  }, '')
}

const deleteCookie = (name, path) => {
  setCookie(name, '', -1, path)
}

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/

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 "";
}

对于读取简单的查询字符串,这一行代码可能在最新版本的JavaScript中适用:

let cookies = Object.fromEntries(document.cookie.split(';').map(i=>i.trim().split('=')));

现在你有了一个带有键和值的JavaScript对象。

对于创建,你可以试试这个:

let cookieObject = {foo: 'bar', ping: "pong"}
Object.entries(cookieObject).map((e)=>`${e[0]}=${e[1]}`).join(';')