I am testing a new way (the current one) to deal with dates and get a strange behavior:
the involved date is : 1985-60-72
I had a crash (I tested my date against Nil) in the beginning, then the application silently quit.
I was able to found the bad date using System.DebugLog Row_Idx to get the line where the error lies.
So, I exit the Loop before that value and test all two other dates (in case of another error). There was none.
The used code to read the date is:
// Crée une variable DateTime
Var bDate_Time As DateTime = DateTime.Now // French format: JJ/MM/AAAA
// Asssigne la date de naissance à la variable
bDate_Time = row.Column("Date_Birth").DateTimeValue
If bDate_Time <> Nil Then
// Affiche la date à la française (JJ/MM/AAAA)
Liste.CellTextAt(Row_Idx,7) = bDate_Time.ToString(French_Loc, DateTime.FormatStyles.Short, DateTime.FormatStyles.None)
Else
System.DebugLog "Mauvaise date: " + row.Column("Date_Birth").StringValue
End If
Your problem seems to be a bad DateTime object, not a nil one. Try … Catch would catch subsequent errors.
Having said that, how did that bad date get into your database in the first place? I would start with making sure that only well-formed dates get entered into the database so I don’t need to worry about possibly illegal dates fetched from the database.
Assure intercepting some conversion error using try/catch:
Var bDate_Time As DateTime
Try
bDate_Time = row.Column("Date_Birth").DateTimeValue // must be saved as YYYY-MM-DD
Catch
bDate_Time = Nil // Bad date/time field, not a valid YYYY-MM-DD
End
If bDate_Time <> Nil Then
// Affiche la date à la française (JJ/MM/AAAA)
Liste.CellTextAt(Row_Idx,7) = bDate_Time.ToString(French_Loc, DateTime.FormatStyles.Short, DateTime.FormatStyles.None)
Else
System.DebugLog "Mauvaise date: " + row.Column("Date_Birth").StringValue
End If
But the previous code should not be “Silent”. It should fire some exception.
That is the right question. I do not know. Until now, one have to use three Popups to set the date…
I skipped the reading for tat column and read the other two: no bad date.
I finished lunch, and I checked the DateTime documentation: No Nil nor Try… in the page !
@Rick: left silently
I do not understand. It is cold today, so that may be my brain not working correctly. Or simply my exit code before the error arise and me forgetting what I’ve done !
For the bad date: its an impossible bad date; if it was 1985-02-29 or 1985-06-31, I would understand but month #60 (06 ?) and day #72 (no idea) !!!
You don’t strictly need to use Try. One could even argue that you shouldn’t as handling errors with Try … Catch is sometimes just lazy – writing code that doesn’t prevent errors before they are happening so one has to catch the ensuing exceptions with Try … Catch. But then again, more often than not it is simpler to do it this way, and sometimes it’s the only way.
In this case you have a choice: You can code defensively, making sure the date is valid before assigning it to DateTime and thus obviating the Try … Catch block. Or you can just go ahead and take care that a possible exception gets handled gracefully. Either approach is fine.
I don’t know about Sascha’s age or yours but I’ve just turned 67. Not a youngster anymore I’m afraid but I know that reading the documentation carefully is not an option – it’s a must. At times the documentation fails us but when it doesn’t we should take heed.
o.
