//设置cookie
function setCookie(sName,sValue,expireHours) {
	var cookieString = sName + "=" + escape(sValue);
	if (expireHours>0) {
		 var date = new Date();
		 date.setTime(date.getTime + expireHours * 3600 * 1000);
		 cookieString = cookieString + "; expire=" + date.toGMTString();
	}
	document.cookie = cookieString;
}

//获取cookie
function getCookie(sName) {
  var aCookie = document.cookie.split("; ");
  for (var j=0; j < aCookie.length; j++){
	var aCrumb = aCookie[j].split("=");
	if (escape(sName) == aCrumb[0])
	  return unescape(aCrumb[1]);
  }
  return null;
}