Меню

File exists php не работает

file_exists

(PHP 4, PHP 5, PHP 7, PHP 8)

file_exists — Проверяет существование указанного файла или каталога

Описание

Проверяет наличие указанного файла или каталога.

Список параметров

Путь к файлу или каталогу.

На платформах Windows, для проверки наличия файлов на сетевых ресурсах, используйте имена, подобные //computername/share/filename или \\computername\share\filename .

Возвращаемые значения

Возвращает true , если файл или каталог, указанный параметром filename , существует, иначе возвращает false .

Данная функция возвращает false для символических ссылок, указывающих на несуществующие файлы.

Проверка происходит с помощью реальных UID/GID, а не эффективных идентификаторов.

Замечание: Так как тип integer в PHP является целым числом со знаком, и многие платформы используют 32-х битные целые числа, то некоторые функции файловых систем могут возвращать неожиданные результаты для файлов размером больше 2 Гб.

Ошибки

В случае неудачного завершения работы генерируется ошибка уровня E_WARNING .

Примеры

Пример #1 Проверка существования файла

if ( file_exists ( $filename )) <
echo «Файл $filename существует» ;
> else <
echo «Файл $filename не существует» ;
>
?>

Примечания

Замечание: Результаты этой функции кешируются. Более подробную информацию смотрите в разделе clearstatcache() .

Начиная с PHP 5.0.0, эта функция также может быть использована с некоторыми обёртками url. Список обёрток, поддерживаемых семейством функций stat() , смотрите в разделе Поддерживаемые протоколы и обёртки.

Смотрите также

  • is_readable() — Определяет существование файла и доступен ли он для чтения
  • is_writable() — Определяет, доступен ли файл для записи
  • is_file() — Определяет, является ли файл обычным файлом
  • file() — Читает содержимое файла и помещает его в массив
  • SplFileInfo

User Contributed Notes 30 notes

Note: The results of this function are cached. See clearstatcache() for more details.

That’s a pretty big note. Don’t forget this one, since it can make your file_exists() behave unexpectedly — probably at production time 😉

file_exists() does NOT search the php include_path for your file, so don’t use it before trying to include or require.

@$result = include $filename;

Yes, include does return false when the file can’t be found, but it does also generate a warning. That’s why you need the @. Don’t try to get around the warning issue by using file_exists(). That will leave you scratching your head until you figure out or stumble across the fact that file_exists() DOESN’T SEARCH THE PHP INCLUDE_PATH.

In response to seejohnrun’s version to check if a URL exists. Even if the file doesn’t exist you’re still going to get 404 headers. You can still use get_headers if you don’t have the option of using CURL..

$file = ‘http://www.domain.com/somefile.jpg’;
$file_headers = @get_headers($file);
if($file_headers[0] == ‘HTTP/1.1 404 Not Found’) <
$exists = false;
>
else <
$exists = true;
>

If you are trying to access a Windows Network Share you have to configure your WebServer with enough permissions for example:

You will get an error telling you that the pathname doesnt exist this will be because Apache or IIS run as LocalSystem so you will have to enter to Services and configure Apache on «Open a session as» Create a new user that has enough permissions and also be sure that target share has the proper permissions.

Hope this save some hours of research to anyone.

With PHP 7.0 on Ubuntu 17.04 and with the option allow_url_fopen=On, file_exists() returns always false when trying to check a remote file via HTTP.

Читайте также:  Как настроить item description

returns always «missing», even for an existing URL.

I found that in the same situation the file() function can read the remote file, so I changed my routine in

This is clearly a bit slower, especially if the remote file is big, but it solves this little problem.

For some reason, none of the url_exists() functions posted here worked for me, so here is my own tweaked version of it.

function url_exists ( $url ) <
$url = str_replace ( «http://» , «» , $url );
if ( strstr ( $url , «/» )) <
$url = explode ( «/» , $url , 2 );
$url [ 1 ] = «/» . $url [ 1 ];
> else <
$url = array( $url , «/» );
>

$fh = fsockopen ( $url [ 0 ], 80 );
if ( $fh ) <
fputs ( $fh , «GET » . $url [ 1 ]. » HTTP/1.1\nHost:» . $url [ 0 ]. «\n\n» );
if ( fread ( $fh , 22 ) == «HTTP/1.1 404 Not Found» ) < return FALSE ; >
else

I wrote this little handy function to check if an image exists in a directory, and if so, return a filename which doesnt exists e.g. if you try ‘flower.jpg’ and it exists, then it tries ‘flower[1].jpg’ and if that one exists it tries ‘flower[2].jpg’ and so on. It works fine at my place. Ofcourse you can use it also for other filetypes than images.

function imageExists ( $image , $dir ) <

$i = 1 ; $probeer = $image ;

Note on openspecies entry (excellent btw, thanks!).

If your server cannot resolve its own DNS, use the following:
$f = preg_replace(‘/www\.yourserver\.(net|com)/’, getenv(‘SERVER_ADDR’), $f);

Just before the $h = @get_headers($f); line.

Replace the extensions (net|com|. ) in the regexp expression as appropriate.

The preg_replace will effectively ‘resolve’ the address for you by assigning $f as follows:
http://10.0.0.125/myfile.gif

If the file being tested by file_exists() is a file on a symbolically-linked directory structure, the results depend on the permissions of the directory tree node underneath the linked tree. PHP under a web server (i.e. apache) will respect permissions of the file system underneath the symbolic link, contrasting with PHP as a shell script which respects permissions of the directories that are linked (i.e. on top, and visible).

This results in files that appear to NOT exist on a symbolic link, even though they are very much in existance and indeed are readable by the web server.

this code here is in case you want to check if a file exists in another server:

function fileExists ( $path ) <
return (@ fopen ( $path , «r» )== true );
>
?>

unfortunately the file_exists can’t reach remote servers, so I used the fopen function.

Here is a simpler version of url_exists:

function url_exists ( $url ) <
$hdrs = @ get_headers ( $url );
return is_array ( $hdrs ) ? preg_match ( ‘/^HTTP\\/\\d+\\.\\d+\\s+2\\d\\d\\s+.*$/’ , $hdrs [ 0 ]) : false ;
>
?>

When using file_exists, seems you cannot do:

foreach ( $possibles as $poss )
<
if ( file_exists ( SITE_RANGE_IMAGE_PATH . $this -> range_id . ‘/ ‘ . $poss . ‘.jpg’ ) )
<
// exists
>
else
<
// not found
>
>
?>

so you must do:

foreach ( $possibles as $poss )
<
$img = SITE_RANGE_IMAGE_PATH . $this -> range_id . ‘/ ‘ . $poss . ‘.jpg’
if ( file_exists ( $img ) )
<
// exists
>
else
<
// not found
>
>
?>

Then things will work fine.

This is at least the case on this Windows system running php 5.2.5 and apache 2.2.3

Not sure if it is down to the concatenation or the fact theres a constant in there, i’m about to run away and test just that.

Читайте также:  Не работает микрофон гугл meet

I was having problems with the file_exists when using urls, so I made this function:

function file_exists_2 ( $filePath )
<
return ( $ch = curl_init ( $filePath )) ? @ curl_close ( $ch ) || true : false ;
>
?>

Cheers!

I made a bit of code that sees whether a file served via RTSP is there or not:

function rtsp_exists ( $url ) <

$server = parse_url ( $url , PHP_URL_HOST );
$port = «554» ;
$hdrs = «DESCRIBE » . $url . » RTSP/1.0″ . «\r\n\r\n» ;

//Open connection (15s timeout)
$sh = fsockopen ( $server , $port , $err , $err_otp , 15 );
//Check connections
if(! $sh ) return false ;
//Send headers
fputs ( $sh , $hdrs );
//Receive data (1KB)
$rtds = fgets ( $sh , 1024 );
//Close socket
fclose ( $sh );

return strpos ( $rtds , «200 OK» ) > 0 ;
>
?>

NB: This function expects the full server-related pathname to work.

For example, if you run a PHP routine from within, for example, the root folder of your website and and ask:

You will get FALSE even if that file does exist off root.

You need to add

to get it to return TRUE — ie : /srv/www/mywebsite.com/public/images/Proofreading_patients.jpg

Older php (v4.x) do not work with get_headers() function. So I made this one and working.

function url_exists ( $url ) <
// Version 4.x supported
$handle = curl_init ( $url );
if ( false === $handle )
<
return false ;
>
curl_setopt ( $handle , CURLOPT_HEADER , false );
curl_setopt ( $handle , CURLOPT_FAILONERROR , true ); // this works
curl_setopt ( $handle , CURLOPT_NOBODY , true );
curl_setopt ( $handle , CURLOPT_RETURNTRANSFER , false );
$connectable = curl_exec ( $handle );
curl_close ( $handle );
return $connectable ;
>
?>

file_exists() will return FALSE for broken links

$ ln -s does_not_exist my_link
$ ls -l
lrwxr-xr-x 1 user group 14 May 13 17:28 my_link -> does_not_exist
$ php -r «var_dump(file_exists(‘my_link’));»
bool(false)

You could use document root to be on the safer side because the function does not take relative paths:

if( file_exists ( $_SERVER < 'DOCUMENT_ROOT' >. «/my_images/abc.jpg» )) <
.
>
?>

Do not forget to put the slash ‘/’, e.g. my doc root in Ubuntu is /var/www without the slash.

I spent the last two hours wondering what was wrong with my if statement: file_exists($file) was returning false, however I could call include($file) with no problem.

It turns out that I didn’t realize that the php include_path value I had set in the .htaccess file didn’t carry over to file_exists, is_file, etc.

// .htaccess php_value include_path ‘/home/user/public_html/’;

// includes lies in /home/user/public_html/includes/

//doesn’t work, file_exists returns false
if ( file_exists ( ‘includes/config.php’ ) )
<
include( ‘includes/config.php’ );
>

//does work, file_exists returns true
if ( file_exists ( ‘/home/user/public_html/includes/config.php’ ) )
<
include( ‘includes/config.php’ );
>
?>

Just goes to show that «shortcuts for simplicity» like setting the include_path in .htaccess can just cause more grief in the long run.

The code can be used to t a filename that can be used to create a new filename.

function generateRandomString ( $length = 8 )
<
$string = «» ;

//character that can be used
$possible = «0123456789bcdfghjkmnpqrstvwxyz» ;

for( $i = 0 ; $i $length ; $i ++)
<
$char = substr ( $possible , rand ( 0 , strlen ( $possible )- 1 ), 1 );

if (! strstr ( $string , $char ))
<
$string .= $char ;
>
>

function randomFile ( $folder = » , $extension = » )
<
$folder = trim ( $folder );
$folder = ( $folder == » ) ? ‘./’ : $folder ;

//check if directory exist
if (! is_dir ( $folder ))

Читайте также:  Gcode g92 не работает

//generate a filepath
$filepath = $folder . «/» . generateRandomString ( 128 ) . $extension ;

//check if that filepath already exist, if it exist if generates again
//till if gets one that doesn’t exist
while( file_exists ( $filepath ))
<
$filepath = $folder . «/» . generateRandomString ( 128 ) . $extension ;
>

My way of making sure files exist before including them is as follows (example: including a class file in an autoloader):

function __autoload ( $name )
<
$path = explode ( «:» , ini_get ( ‘include_path’ )); //get all the possible paths to the file (preloaded with the file structure of the project)
foreach( $path as $tryThis )
<
//try each possible iteration of the file name and use the first one that comes up
// name.class.php first
$exists = file_exists ( $tryThis . ‘/’ . $name . ‘.class.php’ );
if ( $exists )
<
include_once( $name . ‘.class.php’ );
return;
>

//ok that didn’t work, try the other way around
$exists = file_exists ( $tryThis . ‘/’ . ‘class.’ . $name . ‘.php’ );
if ( $exists )
<
include_once( ‘class.’ . $name . ‘.php’ );
return;
>

//neither did that. let’s try as an inc.php
$exists = file_exists ( $tryThis . ‘/’ . $name . ‘.inc.php’ );
if ( $exists )
<
include_once( $name . ‘.inc.php’ );
return;
>
>

// can’t find it.
die( «Class $name could not be found!» );
>
?>

file_exists() is vulnerable to race conditions and clearstatcache() is not adequate to avoid it.

The following function is a good solution:

function file_exists_safe ( $file ) <
if (! $fd = fopen ( $file , ‘xb’ )) <
return true ; // the file already exists
>
fclose ( $fd ); // the file is now created, we don’t need the file handler
return false ;
>
?>

The function will create a file if non-existent, following calls will fail because the file exists (in effect being a lock).

IMPORTANT: The file will remain on the disk if it was successfully created and you must clean up after you, f.ex. remove it or overwrite it. This step is purposely omitted from the function as to let scripts do calculations all the while being sure the file won’t be «seized» by another process.

NOTE: This method fails if the above function is not used for checking in all other scripts/processes as it doesn’t actually lock the file.
FIX: You could flock() the file to prevent that (although all other scripts similarly must check it with flock() then, see https://www.php.net/manual/en/function.flock.php). Be sure to unlock and fclose() the file AFTER you’re done with it, and not within the above function:

function create_and_lock ( $file ) <
if (! $fd = fopen ( $file , ‘xb’ )) <
return false ;
>
if (! flock ( $fd , LOCK_EX | LOCK_NB )) < // may fail for other reasons, LOCK_NB will prevent blocking
fclose ( $fd );
unlink ( $file ); // clean up
return false ;
>
return $fd ;
>

if ( $lock = create_and_lock ( «foo.txt» )) <
// do stuff
flock ( $fd , LOCK_UN ); // unlock
fclose ( $fd ); // close
>
?>

SEE ALSO: https://linux.die.net/man/2/open about O_CREAT|O_EXCL (which is used with the ‘x’ modifier for fopen()) and problems with NFS

If checking for a file newly created by an external program in Windows then file_exists() does not recognize it immediately. Iy seems that a short timeout may be required.

500000) break; // wait a moment
>

if (file_exists($file)) // now should be reliable
?>

Источник

Adblock
detector