C#从datatable中检索满足日期类型条件的记录

     DataRow drrow = ();

        drrow["NMSAlertid"] = 3300165;
        drrow["platformName"] = "成都6险";
        drrow["carrieroperatorName"] = "九2移动";
        drrow["ipAddr"] = "179.16.0.39";
        drrow["phoneNum"] = "15000926250";
        drrow["sendTime"] = "2018-7-17 16:02:49";
        drrow["findTimes"] = 1;

        (drrow);

        string strYestoryNow = (-1).ToString();
        string filterExpression = ("sendTime<=#{0}#", strYestoryNow);
        DataRow[] drDelete = (filterExpression);
        foreach (DataRow dr in drDelete)
        {
            (dr);
            ();
        }