Throwing date errors

[harris79]

I have written a small app which converts day number (1-366) to actual date and vice-versa. It works OK, so I started to think what would happen if the user types an invalid date (29/02/2010 or 33/09/2010 etc) and how do I detect this.

If I do a DateDiff on the input date, I can throw and trap these errors. Great.
But this seems like a bodge to me. After all I'm not interested in the output from the DateDiff.

I was wondering how other people would go about detecting this type of error, without having to code every eventuality?



Steve

 

[ousoonerjoe]

Start with a MaskedTextBox to handle the format and data type validation. Pass the ValidateText value to a variable with data type Date. If DateVariable.Ticks = 0 then the value was invalid. The only issue you still have to contend with is 10/10/5555 is still a legitimate date, but may not a be a viable date for the record at hand. It's not perfect, but has worked for us so far.

			RecDate = txtRecvDate.ValidateText
			If RecDate.Ticks = 0 Then
				StatBarEllipse(txtMsg, "Invalid Receiving Date. Correct and try again.", True)
				txtRecvDate.SelectAll()
				txtRecvDate.Focus()
				Exit Try
			End If

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Stubbornness is a virtue -- if you are right. --Chuck Noll
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[harris79]

ousoonerjoe thanks for this.

I had been using a string for the input date, and then splitting it into day, month & year to work out the day number. Using a date type allowed me to use DatePart to get the number, 1 line of code replaced about 70!

Steve