I need a regular expression that will detect a filename from a string - see if it ends with .pdf, or .PDF - case insensitive. Should even match .Pdf or any variant of pdf in case the user has messy filenames.
This will be used in PHP 5. I know I can make a bunch of rows to test against each case, but I'm sure there's a more elegant way to do this.
There is nothing wrong with a regex, but there is also a ready-made function for dissecting a path and extracting the extension from it:
echo pathinfo("/path/to/myfile.txt", PATHINFO_EXTENSION); //.txt
pathinfo() will work. If you compare the lowercase version against "pdf", you will know whether you need to add the extension or not. Whether what you use is a full path, or a pure file name, should be meaningless to pathinfo().print_r(pathinfo("somefile (2).test.txt.pdf")); works as expected for me. realpath() depends on the specified path actually existing; pathinfo() does not.how about this one. I dont know what language you are using but here is a regex for matching anything ending in .pdf
.+([.][Pp][Dd][Ff]){1}
my bad. Im half asleep. PHP it is. dont know php but that regex should work
another possibility is to tolower the extension
strtolower(pathinfo("/path/file.pDf", PATHINFO_EXTENSION)) == ".pdf"
As others have noted, extracting the extension would work, otherwise you can do something like this.
preg_match('/.*\.pdf/i', "match_me.pDf", $matches);
/.*\.pdf/i needs an end-of-string anchor. Otherwise it matches: file.pdflipingout.txtIf your string consists of a single filename here is a simple regex solution:
if (preg_match('/\.pdf$/i', $filename)) {
// Its a PDF file
}
