javascript 写入cookie读取 cookie以及解码cookie

javascript教程 写入cookie读取 cookie以及解码cookie
function writeCookie(name, value, hours){
 var expire = "";
 if(hours != null){
  expire = new Date((new Date()).getTime() + hours * 3600000);
  expire = "; expires=" + expire.toGMTString();
 }
 document.cookie = name + "=" + escape(value) + expire;
}

//读取cookie
function readCookie(name){
 var cookieValue = "";
 var search = name + "=";
 if(document.cookie.length > 0){
  offset = document.cookie.indexOf(search);
  if (offset != -1){
   offset += search.length;
   end = document.cookie.indexOf(";", offset);
   if (end == -1) end = document.cookie.length;
   cookieValue = unescape(document.cookie.substring(offset, end))
  }
 }
 return cookieValue;
}

//读取cookie 带解码
function readCookieDecode(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 decodeURIComponent(c.substring(nameEQ.length,c.length));
        }
        return null;
}