detecting empty 'input type=file' fields?

[darrel]

I have some INPUT TYPE=FILE fields on a page. There are four of them and I'd
like to validate them. They can either be empty, or need a certain filename.

This is what I am doing:

if (fileUpload_instDOC.PostedFile.FileName.length = 0 OR
lcase(right(fileUpload_instDOC.PostedFile.FileName, 3)) = "doc")
I'm checking to see if it is a word document, or empty.

The problem is the empty part. I can't get that to work. It seems to be
ignoring that completely.

-Darrel

 

[Karl Seguin]

Try using fileUpload_instDoc.PostedFile.ContentLength

you should also use OrElse instead of just Or, since it's short-circuited
resulting is faster (by nanoseconds) code and (more importantly) more
readable..

Karl

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come!)

 

[Kevin Spencer]

Hi Darrel,

Here's a tip regarding File Upload elements: Validate on the client. Why?
Because the file size may be quite large for all you know, and if you upload
it before validation, the entire file will be uploaded before it is
verified. If it is not verified, the correct file will then have to be
uploaded. This will cause a performance drag on the client (read "slow
things down").

--
HTH,

Kevin Spencer
Microsoft MVP
..Net Developer
What You Seek Is What You Get.

 

[darrel]

Here's a tip regarding File Upload elements: Validate on the client.

Well, this is actually set for client-side validation. It's a good tip,
though.

-Darrel

 

[darrel]

The problem is the empty part. I can't get that to work. It seems to be

ignoring that completely.

I'm an idiot. This was a user error issue. Thanks for the help, Karl and
Kevin!

-Darrel