public static void CheckAdmin(string groupID, string userid)
{
string key = string.Format("{0}{1}@{2}", CacheHelper.MembershipPrefix, userid, groupID);
if (CacheHelper.Contains(key) && "admin".Equals(CacheHelper.Get <string>(key)))
{
return;
}
_groupManager.CheckAdmin(groupID, userid);
CacheHelper.Add(key, "admin");
}