0不能做除数

wwwroot/main/Procedure/test14/demo.ashx

@@ -760,7 +760,7 @@ public class demo : IHttpHandler
                             Select(ex => ex.Field<decimal>("成检不合格数")).FirstOrDefault();
                     DataRow dr = restultDay.NewRow();
                     dr["出窑数"] = kilnexits;
-                    dr["施釉合格率"] = ((kilnexits - unqualified) / kilnexits).ToString("p2");
+                    dr["施釉合格率"] = (kilnexits - unqualified)<=0?"0":((kilnexits - unqualified) / kilnexits).ToString("p2");
                     dr["日期"] = type == "yyyymmdd" ? dateTime.ToString("MM") + "." + dateTime.AddDays(-i).ToString("dd") :
                             dateTime.ToString("yy") + "." + dateTime.AddMonths(-i).ToString("MM");
                     restultDay.Rows.Add(dr);