IT:AD:JScript:HowTo:Cookies

Plain old JS:

function setCookie(name,value,days) {
  if (days) {
    var date = new Date();
    date.setTime(date.getTime()+(days*24*60*60*1000));
    var expires = "; expires="+date.toGMTString();
  }
  else var expires = "";
  document.cookie = name+"="+value+expires+"; path=/";
}

function getCookie(name) {
  var nameEQ = name + "=";
  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(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
  }
  return null;
}

function deleteCookie(name) {
  setCookie(name,"",-1);
}

• Cookies impact performance:
  • Cookies are sent with every request.
    • So if the image has 50 images, it gets sent 50 times…
    • Hence why Google Page Speed or Yahoo's YSlow recommend sending static content from different, cookie-free, domains.
  • Consider using the Cookie path feature if you can't reduce the size.