Other - Regex to validate file extension is pdf or no file extension (a Mac File)

The following regex works for forcing all files to be pdf, but breaks/doesn't work when a Mac user uploads a pdf file with no file extension: ^.+\.((?:[pP][dD][fF]))$

Any suggestions for a regex that works for either a PDF file extension or no file extension?

Given a name like "document" there is no possible way to tell if it's a PDF or not. Really. Think about it for a second.
Now if you can look at the file contents, maybe with some MIME-magic tool, then you've got yourself a new option.

True that. Actually checking the mime type server side doing exactly that - that's a little magic. What I'm looking at is checking on the client side and just focusing on the extension. Know it has its weaknesses, but I think an extension check will be helpful for a majority of the documents that are uploaded to the site. For the others, I will relie on the server side verfication.

How are you doing the test?

Code:

php?
if (preg_match('/^.+\.((?:[pP][dD][fF]))$/', $subject)) {
	# Successful match
} else {
	# Match attempt failed
}

Code:

perl?
if ($subject =~ m/^.+\.((?:[pP][dD][fF]))$/) {
	# Successful match
} else {
	# Match attempt failed
}

Working in C#/asp.net. Didn't work. Thanks, though.

Ok, Then try this:

Works for selecting against the following file names:

*.doc
*.pdf

Does not work for a file with no extension: example -
e.g. 2012DetailedSessionOutline

Using ASP.NET regular expression validation control.

Thanks for the help.

I'm not sure what you mean when you say it doesn't work, this matches if the file name ends in ".pdf" so any other file name will hit the else(i.e. no match) condition, also check out:
http://regexpal.com/

Also check out this info:
http://msdn.microsoft.com/en-us/library/aa479405.aspx