Get cookie by name

Question

I have a getter to get the value from a cookie.

Now I have 2 cookies by the name shares= and by the name obligations= .

I want to

Answer 1

function getCookie(name) {
    var pair = document.cookie.split('; ').find(x => x.startsWith(name+'='));
    if (pair)
       return pair.split('=')[1]
}

Answer 2

Use object.defineProperty

With this, you can easily access cookies

Object.defineProperty(window, "Cookies", {
    get: function() {
        return document.cookie.split(';').reduce(function(cookies, cookie) {
            cookies[cookie.split("=")[0]] = unescape(cookie.split("=")[1]);
            return cookies
        }, {});
    }
});

From now on you can just do:

alert( Cookies.obligations );

This will automatically update too, so if you change a cookie, the Cookies will change too.

Answer 3

The methods in some of the other answers that use a regular expression do not cover all cases, particularly:

1. When the cookie is the last cookie. In this case there will not be a semicolon after the cookie value.
2. When another cookie name ends with the name being looked up. For example, you are looking for the cookie named "one", and there is a cookie named "done".
3. When the cookie name includes characters that are not interpreted as themselves when used in a regular expression unless they are preceded by a backslash.

The following method handles these cases:

function getCookie(name) {
    function escape(s) { return s.replace(/([.*+?\^$(){}|\[\]\/\\])/g, '\\$1'); }
    var match = document.cookie.match(RegExp('(?:^|;\\s*)' + escape(name) + '=([^;]*)'));
    return match ? match[1] : null;
}

This will return null if the cookie is not found. It will return an empty string if the value of the cookie is empty.

Notes:

1. This function assumes cookie names are case sensitive.
2. document.cookie - When this appears on the right-hand side of an assignment, it represents a string containing a semicolon-separated list of cookies, which in turn are name=value pairs. There appears to be a single space after each semicolon.
3. String.prototype.match() - Returns null when no match is found. Returns an array when a match is found, and the element at index [1] is the value of the first matching group.

Regular Expression Notes:

1. (?:xxxx) - forms a non-matching group.
2. ^ - matches the start of the string.
3. | - separates alternative patterns for the group.
4. ;\\s* - matches one semi-colon followed by zero or more whitespace characters.
5. = - matches one equal sign.
6. (xxxx) - forms a matching group.
7. [^;]* - matches zero or more characters other than a semi-colon. This means it will match characters up to, but not including, a semi-colon or to the end of the string.

Answer 4

Apparently MDN has never heard of the word-boundary regex character class \b, which matches contiguous \w+ that is bounded on either side with \W+:

getCookie = function(name) {
    var r = document.cookie.match("\\b" + name + "=([^;]*)\\b");
    return r ? r[1] : null;
};

var obligations = getCookie('obligations');

Answer 5

Get cookie by name just pass the name of cookie to below function

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 "";
}

Answer 6

I have done it this way. so that i get an object to access to separate the values.With this u can pass the cookie to the parent and then you can access your values by the keys like

var cookies=getCookieVal(mycookie);
alert(cookies.mykey);
function getCookieVal(parent) {
            var cookievalue = $.cookie(parent).split('&');
            var obj = {};
            $.each(cookievalue, function (i, v) {
                var key = v.substr(0, v.indexOf("="));
                var val = v.substr(v.indexOf("=") + 1, v.length);

                obj[key] = val;

            });
            return obj;
        }