c#中时间段查询

//根据时间段查询 public IList FindByTime(DateTime startdt, DateTime enddt) { string _startdt = startdt.Year + "-" + startdt.Month + "-" + startdt.Day; string _enddt = enddt.Year + "-" + enddt.Month + "-" + enddt.Day; string sql = "select * from operatorlog where operatedt >=to_date('" + _startdt + "','YYYY-MM-DD HH:MI:SS') and operatedt <=to_date('" + _enddt + "','YYYY-MM-DD HH:MI:SS') order by operatedt desc"; return base.FindBySQLQuery(sql, "Operatorlog", typeof(Operatorlog)); } //根据开始时间查询 public IList FindByStartTime(DateTime startdt) { string _startdt = startdt.Year + "-" + startdt.Month + "-" + startdt.Day; string sql = "select * from operatorlog where operatedt>=to_date('" + _startdt + "','YYYY-MM-DD HH:MI:SS') order by operatedt desc"; return base.FindBySQLQuery(sql, "Operatorlog", typeof(Operatorlog)); } //根据结束时间查询 public IList FindByendTime(DateTime enddt) { string _enddt = enddt.Year + "-" + enddt.Month + "-" + enddt.Day; string sql = "select * from operatorlog where operatedt<=to_date('" + _enddt + "','YYYY-MM-DD HH:MI:SS') order by operatedt desc"; return base.FindBySQLQuery(sql, "Operatorlog", typeof(Operatorlog)); }