Here a nice little cookie wrapper. It’s mainly based on the Quirksmode code with some nice Prototype style.

Have a look:

var cookieJar = Class.create();
cookieJar.prototype = {
initialize: function() {},
write: function(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=/';
},
writeJSON: function(name,value,days) {
var JSONvalue = $H(value).toJSON();
this.write(name,JSONvalue,days);
},
read: function(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 false;
},
readJSON: function(name) {
var value = this.read(name) || '{}';
value = value.evalJSON();
return value;
},
erase: function (name) {
this.create(name,"",-1);
}
};
cJar = new cookieJar();