public static Dictionary<string, DateTime> GetBusinessTime()
 {
     Dictionary<string, DateTime> dictionary = new Dictionary<string, DateTime>();
     DataContextDataContext dc = new DataContextDataContext();
     ISingleResult<select_all_businesstimeResult> rs = dc.select_all_businesstime();
     foreach (select_all_businesstimeResult r in rs)
     {
         dictionary.Add(r.keyword, r.time);
     }
     return dictionary;
 }