。

The Document property cookie lets you read and write cookies associated with the document. It serves as a getter and setter for the actual values of the cookies.

var c = 'Yash' + '=' + 'Yash-777';
document.cookie = c; // Set the value: "Yash=Yash-777"
document.cookie      // Get the value:"Yash=Yash-777"

来自谷歌GWT项目cookie .java类本机代码。我准备了以下函数来对Cookie执行操作。

函数以JSON对象的形式获取所有cookie列表。

var uriEncoding = false;
function loadCookiesList() {
    var json = new Object();
    if (typeof document === 'undefined') {
        return json;
    }

    var docCookie = document.cookie;
    if (docCookie && docCookie != '') {
      var crumbs = docCookie.split('; ');
      for (var i = crumbs.length - 1; i >= 0; --i) {
        var name, value;
        var eqIdx = crumbs[i].indexOf('=');
        if (eqIdx == -1) {
          name = crumbs[i];
          value = '';
        } else {
          name = crumbs[i].substring(0, eqIdx);
          value = crumbs[i].substring(eqIdx + 1);
        }
        if (uriEncoding) {
          try {
            name = decodeURIComponent(name);
          } catch (e) {
            // ignore error, keep undecoded name
          }
          try {
            value = decodeURIComponent(value);
          } catch (e) {
            // ignore error, keep undecoded value
          }
        }
        json[name] = value;
      }
    }
    return json;
 }

设置并获取具有特定名称的Cookie。

function getCookieValue(name) {
    var json = loadCookiesList();
    return json[name];
}

function setCookie(name, value, expires, domain, path, isSecure) {
    var c = name + '=' + value;
    if ( expires != null) {
        if (typeof expires === 'number') {
            // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/now
            var timeInMs = Date.now();
            if (expires > timeInMs ) {
                console.log("Seting Cookie with provided expire time.");
                c += ';expires=' + (new Date(expires)).toGMTString();
            } else if (expires < timeInMs) {
                console.log("Seting Cookie with Old expire time, which is in Expired State.");
                timeInMs = new Date(timeInMs + 1000 * expires);
                c += ';expires=' + (new Date(timeInMs)).toGMTString();
            }
        } else if (expires instanceof window.Date) {
            c += ';expires=' + expires.toGMTString();
        }
    }

    if (domain != null && typeof domain == 'string')
      c += ';domain=' + domain;
    if (path != null && typeof path == 'string')
      c += ';path=' + path;
    if (isSecure != null && typeof path == 'boolean')
      c += ';secure';

    if (uriEncoding) {
        encodeURIComponent(String(name))
            .replace(/%(23|24|26|2B|5E|60|7C)/g, decodeURIComponent)
            .replace(/[\(\)]/g, escape);
        encodeURIComponent(String(value))
            .replace(/%(23|24|26|2B|3A|3C|3E|3D|2F|3F|40|5B|5D|5E|60|7B|7D|7C)/g, decodeURIComponent);

    }
    document.cookie = c;
}

function removeCookie(name) {
    document.cookie = name + "=;expires=Fri, 02-Jan-1970 00:00:00 GMT"; 
}
function removeCookie(name, path) {
    document.cookie = name + "=;path=" + path + ";expires=Fri, 02-Jan-1970 00:00:00 GMT";
}

检查cookie名称是否有效:不能包含'='，';'，'，'或空格。不能以$开头。

function isValidCookieName(name) {
    if (uriEncoding) {
      // check not necessary
      return true;
    } else if (name.includes("=") || name.includes(";") || name.includes(",") || name.startsWith("$") || spacesCheck(name) ) {
      return false;
    } else {
      return true;
    }
}
// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/test
function spacesCheck(name) {
    var whitespace = new RegExp('.*\\s+.*');
    var result = whitespace.test(name);
    console.log("Name:isContainSpace = ", name, ":", result);
    return result;
}

测试步骤检查以上功能:

setCookie("yash1", "Yash-777");
setCookie("yash2", "Yash-Date.now()", Date.now() + 1000 * 30);
setCookie("yash3", "Yash-Sec-Feature", 30);
setCookie("yash4", "Yash-Date", new Date('November 30, 2020 23:15:30'));

getCookieValue("yash4"); // Yash-Date
getCookieValue("unknownkey"); // undefined

var t1 = "Yash", t2 = "Y    ash", t3 = "Yash\n";
spacesCheck(t1); // False
spacesCheck(t2); // True
spacesCheck(t3); // True

我更喜欢在cookie上使用一个正则表达式匹配:

window.getCookie = function(name) {
  var match = document.cookie.match(new RegExp('(^| )' + name + '=([^;]+)'));
  if (match) return match[2];
}

也可以作为函数使用，检查下面的代码。

function check_cookie_name(name) 
    {
      var match = document.cookie.match(new RegExp('(^| )' + name + '=([^;]+)'));
      if (match) {
        console.log(match[2]);
      }
      else{
           console.log('--something went wrong---');
      }
   }

感谢Scott Jungwirth的评论。

cookie示例: JS:

document.cookies = {
   create : function(key, value, time){
     if (time) {
         var date = new Date();
         date.setTime(date.getTime()+(time*24*60*60*1000));
         var expires = "; expires="+date.toGMTString();
     }
     else var expires = "";
     document.cookie = key+"="+value+expires+"; path=/";
   },
   erase : function(key){
     this.create(key,"",-1);
   },
   read : function(key){
     var keyX = key + "=";
     var ca = document.cookie.split(';');
     for(var i=0;i < ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0)==' ') c = c.substring(1,c.length);
          if (c.indexOf(keyX) == 0) return   c.substring(keyX.length,c.length);
     }
     return null;
   }
}

使用json或xml存储数组和对象

我的解决方案是:

function getCookieValue(cookieName) {
    var ca = document.cookie.split('; ');
    return _.find(ca, function (cookie) {
        return cookie.indexOf(cookieName) === 0;
    });
}

该函数使用Underscorejs _.find-函数。如果cookie名称不存在，则返回undefined

我喜欢使用闭包按名称获取cookie值。下面的闭包将允许您通过名称获取cookie值，但只有在更新了cookie字符串时才会解析cookie字符串。

您可以通过以下方法检索cookie的值:

var foo = cookies.get( "bar" );

代码:

var cookies = ( function() {
    var cookieString = null;
    var cookieArray = [];

    function getValOf( name ) {
        if ( newCookies() ) {
            parseCookieString()
        }
        return cookieArray[ name ];
    }

    // Check if new cookies have been added
    function newCookies() {
        return cookieString === document.cookie;
    }

    function parseCookieString() {
        cookieString = document.cookie;

        // Separate cookies
        var cookies = cookieString.split( ";" );

        // Empty previous cookies
        cookieArray = [];

        // Update cookieArray with new name-value pairs
        for ( var i in cookies ) {

            // Separate name and value
            var nameVal = cookies[ i ].split( "=" );
            var name = nameVal[ 0 ].trim();
            var value = nameVal[ 1 ].trim();

            // Add cookie name value pair to dictionary
            cookieArray[ name ] = value;
        }
    }

    return {

        /**
         * Returns value or undefined
         */
        get: function( name ) {
            return getValOf( name );
        }  
    };
})();

我会这样做:

function getCookie(cookie){
  return cookie
    .trim()
    .split(';')
    .map(function(line){return line.split(',');})
    .reduce(function(props,line) {
      var name = line[0].slice(0,line[0].search('='));
      var value = line[0].slice(line[0].search('='));
      props[name] = value;
      return props;
    },{})
}

这将以对象的形式返回cookie。

然后你可以这样调用它:

getCookie(document.cookie)['shares']