如果你使用jQuery，我建议你使用这个插件:

https://github.com/carhartl/jquery-cookie https://github.com/carhartl/jquery-cookie/blob/master/jquery.cookie.js

<script type="text/javascript"
 src="//cdnjs.cloudflare.com/ajax/libs/jquery-cookie/1.4.1/jquery.cookie.min.js">

所以你可以这样读cookie:

var value = $.cookie("obligations");

你也可以写cookie:

$.cookie('obligations', 'new_value');
$.cookie('obligations', 'new_value', { expires: 14, path: '/' });

删除cookie:

$.removeCookie('obligations');

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 );
        }  
    };
})();

Kirlich给出了一个很好的解决方案。然而，当有两个cookie值具有相似的名称时，它会失败，这里有一个简单的修复这种情况:

function getCookie(name) {
  var value = "; " + document.cookie;
  var parts = value.split("; " + name + "=");
  if (parts.length >= 2) return parts.pop().split(";").shift();
}

const cookies = 'key1=chocolate; key2=iceCream; key3=cookies;';

// convert string into array with split
const arrCookies = cookies.split('; '); // [ 'key1=chocolate', 'key2=iceCream', 'key3=cookies' ]

// split key value by equal sign
const arrArrCookiesKeyValue = arrCookies.map(cookie => [cookie.split('=')]);  // [[['key1', 'chocolate']], ...']

// make an object with key value
const objectKeyValueCookies = {}; // { key1: 'chocolate', key2: 'iceCream', key3: 'cookies;' }
for (let arr of arrArrCookiesKeyValue) {
    objectKeyValueCookies[arr[0][0]] = arr[0][1];
}

// find the key in object
const findValueByKey = (key = null, objectCookies) => objectCookies[key];
console.log(findValueByKey('key2', objectKeyValueCookies)); // chocolate

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。

function GetCookieValue(name) {
    var found = document.cookie.split(';').filter(c => c.trim().split("=")[0] === name);
    return found.length > 0 ? found[0].split("=")[1] : null;
}