PHP Case Insensitive Version of file_exists()

I'm trying to think of the fastest way to implement a case insensitive file_exists function in PHP. Is my best bet to enumerate the file in the directory and do a strtolower() t开发者_如何学Goo strtolower() comparison until a match is found?

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I used the source from the comments to create this function. Returns the full path file if found, FALSE if not.

Does not work case-insensitively on directory names in the filename.

function fileExists($fileName, $caseSensitive = true) {

    if(file_exists($fileName)) {
        return $fileName;
    }
    if($caseSensitive) return false;

    // Handle case insensitive requests            
    $directoryName = dirname($fileName);
    $fileArray = glob($directoryName . '/*', GLOB_NOSORT);
    $fileNameLowerCase = strtolower($fileName);
    foreach($fileArray as $file) {
        if(strtolower($file) == $fileNameLowerCase) {
            return $file;
        }
    }
    return false;
}

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This question is a few years old but it is linked to several as duplicates, so here is a simple method.

Returns false if the $filename in any case is not found in the $path or the actual filename of the first file returned by glob() if it was found in any case:

$result = current(preg_grep("/^".preg_quote($filename)."$/i", glob("$path/*")));

• Get all files in the path glob
• Grep for the $filename in any case i is case-insensitive
• current returns the first filename from the array

Remove the current() to return all matching files. This is important on case-sensitive filesystems as IMAGE.jpg and image.JPG can both exist.

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In Unix file names are case sensitive, so you won't be able to do a case insensitive existence check without listing the contents of the directory.

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Your approach works.
Alternatively you can use glob to get the list of all files and directories in the present working directory in an array, use array_map to apply strtolower to each element and then use in_array to check if your file(after applying strtolower) exists in the array.

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I ran into the same issue when we migrated from IIS to apache. Below is the piece I whipped up. It returns either the correct path as a string or false.

function resolve_path($path)
{
    $is_absolute_path = substr($path, 0, 1) == '/';
    $resolved_path = $is_absolute_path ? '/' : './';
    $path_parts = explode('/', strtolower($path));

    foreach ($path_parts as $part)
    {
        if (!empty($part))
        {
            $files = scandir($resolved_path);

            $match_found = FALSE;

            foreach ($files as $file)
            {
                if (strtolower($file) == $part)
                {
                    $match_found = TRUE;

                    $resolved_path .= $file . '/';
                }
            }

            if (!$match_found)
            {
                return FALSE;
            }
        }
    }

    if (!is_dir($resolved_path) && !is_file($resolved_path))
    {
        $resolved_path = substr($resolved_path, 0, strlen($resolved_path) - 1);
    }

    $resolved_path = $is_absolute_path ? $resolved_path : substr($resolved_path, 2, strlen($resolved_path));

    return $resolved_path;
}

$relative_path = substr($_SERVER['REQUEST_URI'], 1, strlen($_SERVER['REQUEST_URI']));
$resolved_path = resolve_path($relative_path);

if ($resolved_path)
{
    header('Location: http://' . $_SERVER['SERVER_NAME'] . '/' . $resolved_path);
    die();
}

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AbraCadaver's answer with +7 rating is incorrect, I do not have enough reputation to comment under it, so here is correct solution, based on his answer:

$result = count(preg_grep('/\/'.preg_quote($filename)."$/i", glob("$path/*")));

AbraCadaver's answer is incorrect, because it returns true if you test against file foo.jpg and files like anytext_foo.jpg exist.

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I tuned the function a lil bit more. guess this better for use

function fileExists( $fileName, $fullpath = false, $caseInsensitive = false ) 
{
    // Presets
    $status         = false;
    $directoryName  = dirname( $fileName );
    $fileArray      = glob( $directoryName . '/*', GLOB_NOSORT );
    $i              = ( $caseInsensitive ) ? "i" : "";

    // Stringcheck
    if ( preg_match( "/\\\|\//", $fileName) ) // Check if \ is in the string
    {
        $array    = preg_split("/\\\|\//", $fileName);
        $fileName = $array[ count( $array ) -1 ];
    }

    // Compare String
    foreach ( $fileArray  AS $file )
    {
        if(preg_match("/{$fileName}/{$i}", $file))
        {
            $output = "{$directoryName}/{$fileName}";
            $status = true;
            break;
        }
    }

    // Show full path
    if( $fullpath && $status )
        $status = $output;

    // Return the result [true/false/fullpath (only if result isn't false)]
    return $status;
}

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For a pure PHP implementation, yes. There's an example in the comments for the file_exists function.

The other option would be to run your script on a case insensitive file system.

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I have improved John Himmelman's function and come up with this:
suppose that i have a catch system \iMVC\kernel\caching\fileCache

function resolve_path($path)
{
    # check if string is valid
    if(!strlen($path)) return FALSE;
    # a primary check
    if(file_exists($path)) return $path;
    # create a cache signiture
    $cache_sig = __METHOD__."@$path";
    # open the cache file
    $fc = new \iMVC\kernel\caching\fileCache(__CLASS__);
    # check cache file and validate it
    if($fc->isCached($cache_sig) && file_exists($fc->retrieve($cache_sig)))
    {
        # it was a HIT!
        return $fc->retrieve($cache_sig);
    }
    # if it is ab
    $is_absolute_path = ($path[0] == DIRECTORY_SEPARATOR);
    # depart the path
    $path_parts = array_filter(explode(DIRECTORY_SEPARATOR, strtolower($path)));
    # normalizing array's parts
    $path_parts = count($path_parts)? array_chunk($path_parts, count($path_parts)) : array();
    $path_parts = count($path_parts[0])?$path_parts[0]:array();
    # UNIX fs style
    $resolved_path = $is_absolute_path ? DIRECTORY_SEPARATOR : ".";
    # WINNT fs style
    if(string::Contains($path_parts[0], ":"))
    {
        $is_absolute_path = 1;
        $resolved_path = $is_absolute_path ? "" : ".".DIRECTORY_SEPARATOR;
    }
    # do a BFS in subdirz
    foreach ($path_parts as $part)
    {
        if (!empty($part))
        {
            $target_path = $resolved_path.DIRECTORY_SEPARATOR.$part;
            if(file_exists($target_path))
            {
                $resolved_path = $target_path;
                continue;
            }
            $files = scandir($resolved_path);

            $match_found = FALSE;

            foreach ($files as $file)
            {   
                if (strtolower($file) == $part)
                {
                    $match_found = TRUE;
                    $resolved_path = $resolved_path.DIRECTORY_SEPARATOR.$file;
                    break;
                }
            }
            if (!$match_found)
            {
                return FALSE;
            }
        }
    }
    # cache the result
    $fc->store($target_path, $resolved_path);
    # retrun the resolved path
    return $resolved_path;
}

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Having found this page from a quick google I used Kirk's solution, however it's slow if you call it multiple times on the same directory, or on a directory that has many files in. This is due to it looping over all the files each time, so I optimised it a little:

function fileExists($fileName) {
    static $dirList = [];
    if(file_exists($fileName)) {
        return true;
    }
    $directoryName = dirname($fileName);
    if (!isset($dirList[$directoryName])) {
        $fileArray = glob($directoryName . '/*', GLOB_NOSORT);
        $dirListEntry = [];
        foreach ($fileArray as $file) {
            $dirListEntry[strtolower($file)] = true;
        }
        $dirList[$directoryName] = $dirListEntry;
    }
    return isset($dirList[$directoryName][strtolower($fileName)]);
}

I dropped the flag to check for case insensitivity as I assume you'd just use file_exists if you didn't need this behaviour, so the flag seemed redundant. I also expect that if you're doing anything beyond a trivial script you'd want to turn this into a class to get more control over the directory list caching, e.g. resetting it, but that's beyond the scope of what I needed and it should be trivial to do if you need it.

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My tuned solution, OS independent, case-insensitive realpath() alternative, covering whole path, named realpathi():

/**
 * Case-insensitive realpath()
 * @param string $path
 * @return string|false
 */
function realpathi($path)
{
    $me = __METHOD__;

    $path = rtrim(preg_replace('#[/\\\\]+#', DIRECTORY_SEPARATOR, $path), DIRECTORY_SEPARATOR);
    $realPath = realpath($path);
    if ($realPath !== false) {
        return $realPath;
    }

    $dir = dirname($path);
    if ($dir === $path) {
        return false;
    }
    $dir = $me($dir);
    if ($dir === false) {
        return false;
    }

    $search = strtolower(basename($path));
    $pattern = '';
    for ($pos = 0; $pos < strlen($search); $pos++) {
        $pattern .= sprintf('[%s%s]', $search[$pos], strtoupper($search[$pos]));
    }
    return current(glob($dir . DIRECTORY_SEPARATOR . $pattern));
}

search filename with glob [nN][aA][mM][eE] pattern seems to be the faster solution

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//will resolve & print the real filename
$path = "CaseInsensitiveFiLENAME.eXt";
$dir  = "nameOfDirectory";

if ($handle = opendir($dir)) {
 while (false !== ($entry = readdir($handle))) {
     if (strtolower($path) == strtolower($entry)){
       echo $entry ;
    }}
    closedir($handle);
}

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Just ran across this today, but didn't like any of the answers here, so I thought I would add my solution ( using SPL and the regex iterator )

function _file_exists( $pathname ){
    if(file_exists($pathname)) return $pathname;

    try{
        $path = dirname( $pathname );
        $file = basename( $pathname );

        $Dir = new \FilesystemIterator( $path, \FilesystemIterator::UNIX_PATHS );
        $regX = new \RegexIterator($Dir, '/(.+\/'.preg_quote( $file ).')$/i', \RegexIterator::MATCH);

        foreach ( $regX as $p ) return $p->getPathname();

    }catch (\UnexpectedValueException $e ){
        //invalid path
    }
    return false;
}

The way I am using it is like so:

 $filepath = 'path/to/file.php';

 if( false !== ( $filepath = _file_exists( $filepath ))){
      //do something with $filepath
 }

This way it will use the built in one first, if that fails it will use the insensitive one, and assign the proper casing to the $filepath variable.

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The other answers might be very resource intensive on large file systems (large number of files to search through). It might be useful to create a temporary table of all the filenames (full path if necessary). Then do a like condition search of that table to get whatever the actual case is.

SELECT actual_file_name
FROM TABLE_NAME
WHERE actual_file_name LIKE 'filename_i_want'