空值BUG修改

UAS_CheckWork/Form1.cs

@@ -97,9 +97,10 @@ namespace UAS_CheckWork
             {
                 //循环获取
                 DataTable dt = new DataTable();
-                string LastDate = dh.getFieldDataByCondition("cardlog", "to_char(max(cl_time),'yyyy-MM-dd HH24:mi:ss')", "cl_address='考勤机数据导入'").ToString();
                 dt.Columns.Add("cl_cardcode");
                 dt.Columns.Add("cl_time");
+                showDataGrid.DataSource = dt;
+                string LastDate = dh.getFieldDataByCondition("cardlog", "to_char(max(cl_time),'yyyy-MM-dd HH24:mi:ss')", "cl_address='考勤机数据导入'").ToString();
                 if (LastDate == "")
                 {
                     LastDate = "1990-01-01 00:00:00";
@@ -142,8 +143,7 @@ namespace UAS_CheckWork
                 }
                 if (cl_time.Count > 0)
                     dh.BatchInsert(sql.ToString(), new string[] { "cl_cardcode", "cl_time" }, cl_cardcode.ToArray(), cl_time.ToArray());
-                allData.DataSource = dt;
-                showDataGrid.DataSource = (DataTable)allData.DataSource;
+                showDataGrid.DataSource = dt;
                 if (dt.Rows.Count > 0)
                 {
                     MessageBox.Show("数据同步成功");