Read cookies with JavaScript

Question

I know how to write/create cookies in JavaScript.........................................................

//Create the cookies
document.cookie = \"Name=\" +          


        

Answer 1

Referring to document.cookie gets you the whole string of cookies. They're separated by semicolons.

var cookies = document.cookie.split(';'); // "cookies" will be an array

You could then make that an object with name->value mapping:

var cookieMap = {};
for (var i = 0; i < cookies.length; ++i) {
  cookies[i].replace(/^\s*([^=]+)=(.*)$/, function(_, name, val) {
    cookieMap[name] = unescape(val);
  });
}

Now you can look at a cookie "mycookie" like this:

var mycookieVal = cookieMap.mycookie;

note this is been edited since its initial broken version - still the same idea but not it should actually work. The idea is that the loop takes each of the parts of document.cookie that were separated by semicolons, and then further splits each of those into a name part (stuff before the "=", except leading spaces) and a "value" part (stuff after the "=" to the end of the cookie part). The value is then stored in the "cookieMap" under the given name.

Answer 2

These are much *much* better references than w3schools (the most awful web reference ever made):

• http://www.quirksmode.org/js/cookies.html
• https://developer.mozilla.org/en-US/docs/Web/API/document.cookie

Examples derived from these references:

// sets the cookie cookie1
document.cookie =
 'cookie1=test; expires=Fri, 3 Aug 2001 20:47:11 UTC; path=/'

// sets the cookie cookie2 (cookie1 is *not* overwritten)
document.cookie =
 'cookie2=test; expires=Fri, 3 Aug 2001 20:47:11 UTC; path=/'

// remove cookie2
document.cookie = 'cookie2=; expires=Thu, 01 Jan 1970 00:00:00 UTC; path=/'

The mozilla reference even has a nice cookie library you can use.

Answer 3

From http://w3schools.com/js/js_cookies.asp

set cookie

function setCookie(c_name,value,expiredays)
{
var exdate=new Date();
exdate.setDate(exdate.getDate()+expiredays);
document.cookie=c_name+ "=" +escape(value)+
((expiredays==null) ? "" : ";expires="+exdate.toUTCString());
}

get cookie

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 "";
}