String not recognized as valid DateTime in IsDate funtion

[jtyoder]

When executing code to determine if a text box contains text that's convertable to a date I get the following error :

 

 

 

A first chance exception of type 'System.FormatExeption' occured in mscorlib.dl.

 

Additional information : String was not recognized as a valid DateTime.

 

 

This happens when executing the code :

 

If IsDate(txtDate.Text) Then .....

 

Oddly enough, when I break the program and run this command in the immediate window the command comes back with a boolean as I expect.

 

Anyone have any ideas?

 

Thanks

 

James

[Derek Stone]

Make sure that the entered string isn't null or equivalent to the String.Empty field. Other than that, that line of code shouldn't be giving you any problems.

[Derek Stone]

Actually, my above statements assumed too much. I attempted to input null (Nothing) and empty (String.Empty) values and the function still returned correctly. I have a feeling that your problem is elsewhere, possibly in that surrounding block of code. If you could post the remainder of your code I'd like to look it over.

[jtyoder]

Not much to show, but here it is :

 

   Private Sub txtPullDate_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles txtPullDate.TextChanged
   'Actions to take when the txtPullDate box changes value
If IsDate(txtPullDate.Text.Trim) Then
 txtPullDate.Text = "The If statment is busted!"

End If
   '---
     End Sub

Edited February 17, 2003 by divil

[Derek Stone]

That code block can (and does) work fine. I just verified it, so I don't know what to tell you.

[Volte]

Where is this IsDate function? The only one I could find in the

object browser was in the MS compat. library, in with the likes of

'UBound' et al.

 

My IsDate function looks something like this:

Public Function IsDate(ByVal d As String)
 Try
   Dim dummy As Date = Date.Parse(d)
   Return True
 Catch
   Return False
 End Try
End Function

[Derek Stone]

IsDate() is a Visual Basic .NET function. You can find its documentation under the language and reference portion of the .NET SDK. I'm guessing it's a mapping to System.Convert or Date.Parse(), using a method similar to yours, above.

[Volte]

It's in the 'Visual Basic Language Reference' portion of the MSDN,

along with UBound, QBColor, RGB and others.

I don't think it's a .NET function at all.

[divil]

The function VolteFace posted is exactly what the VB.NET IsDate function does.

[Volte]

Ah, I see what you mean now. D'oh! Still, is it not better to use a

self-written function over a Microsoft-compat. library function, since

they can only be accessed (easily) from within VB, whereas that

function could be used in C# if it was required?

[Robby]

James, one thing you may consider is, instead of using the TextChanged event maybe use the Leave Event. As the user may want to enter the month in words, ie. Feb 2 2003