Read a javascript cookie by name

Question

I have set a cookie using

document.cookie =      'MYBIGCOOKIE=' + value +      '; expires=' + now.toGMTString() +      '; path=/'; 

Now there are between 5 and 10 cookies set on this site, is there a way to check the value ofthis cookie by name.

if (document.cookie.MYBIGCOOKIE == '1') {     alert('it is 1') } 

Answer 1

Use the RegExp constructor and multiple replacements to clarify the syntax:

function getCook(cookiename)    {   // Get name followed by anything except a semicolon   var cookiestring=RegExp(cookiename+"=[^;]+").exec(document.cookie);   // Return everything after the equal sign, or an empty string if the cookie name not found   return decodeURIComponent(!!cookiestring ? cookiestring.toString().replace(/^[^=]+./,"") : "");   }  //Sample usage var cookieValue = getCook('MYBIGCOOKIE'); 

Answer 2

Unfortunately, Javascript's cookie syntax is nowhere near as nice as that. In fact, in my opinion, it's one of the worst designed parts.

When you try to read document.cookie, you get a string containing all the cookies set. You have to parse the string, separating by the semicolon ; character. Rather than writing this yourself, there are plenty of versions available on the web. My favourite is the one at quirksmode.org. This gives you createCookie, readCookie and deleteCookie functions.