Recipe 19.8 Processing All Files in a Directory
19.8.1 Problem
You want to iterate over all files
in a directory. For example, you want to create a
select box in a form that lists all the files in a
directory.
19.8.2 Solution
Get a directory handle with opendir(
)
and then
retrieve each filename with readdir( ):
$d = opendir('/tmp') or die($php_errormsg);
while (false !== ($f = readdir($d))) {
print "$f\n";
}
closedir($d);
19.8.3 Discussion
The code in the solution tests the return value of readdir(
) with the nonidentity operator
(!==) so that the code works properly with
filenames that evaluate to false, such as a file
named 0.
The function readdir( ) returns each entry in a
directory, whether it is a file, directory, or something else (such
as a link or a socket). This includes the metaentries
"."
(current directory) and ".."
(parent directory). To just return files, use the is_file(
)
function as well:
print '<select name="files">';
$d = opendir('/usr/local/upload') or die($php_errormsg);
while (false !== ($f = readdir($d))) {
if (is_file("/usr/local/upload/$f")) {
print '<option> ' . $f . '</option>';
}
}
closedir($d);
print '</select>';
Because readdir( ) returns only the filename of
each directory entry, not a full pathname, you have to prepend the
directory name to $f before you pass it to
is_file( ).
PHP also has an object-oriented interface to directory
information. The dir( ) function returns an object
on which you can call read( ), rewind(
), and close( ) methods, which act like
the readdir( ), rewinddir( ),
and closedir( ) functions.
There's also a $path property
that contains the full path of the opened directory.
Here's how to iterate through files with the
object-oriented interface:
print '<select name="files">';
$d = dir('/usr/local/upload') or die($php_errormsg);
while (false !== ($f = $d->read())) {
if (is_file($d->path.'/'.$f)) {
print '<option> ' . $f . '</option>';
}
}
$d->close();
In this example, $d->path is
/usr/local/upload.
19.8.4 See Also
Documentation on opendir( ) at
http://www.php.net/opendir, readdir(
) at http://www.php.net/readdir, and
the directory class at
http://www.php.net/class.dir.
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