PHP | readdir() Function

The readdir() function in PHP is an inbuilt function which is used to return the name of the next entry in a directory. The method returns the filenames in the order as they are stored in the filenamesystem.

The directory handle is sent as a parameter to the readdir() function and it returns the entry name/filename on success or False on failure.

Syntax:

readdir(dir_handle)

Parameters Used: The readdir() function in PHP accepts one parameter.

• dir_handle : It is a mandatory parameter which specifies the handle resource previously opened by the opendir() function.

Return Value: It returns the entry name/filename on success, or False on failure.

Errors And Exceptions:

1. If the directory handle parameter is not specified by the user then the last link opened by opendir() is assumed by the readdir() function.
2. Apart from returning Boolean FALSE, the readdir() function may sometimes also return a non-Boolean value which evaluates to FALSE.

Below programs illustrate the readdir() function:

Program 1:

<?php

// opening a directory
$dir_handle = opendir("user/gfg/");

// reading the contents of the directory
while(($file_name = readdir($dir_handle)) !== false)
{
echo("File Name: " . $file_name);
echo "<br>" ;
}

// closing the directory
closedir($dir_handle);
?>

Output:

File Name: gfg.jpg
File Name: ..
File Name: article.pdf
File Name: .
File Name: article.txt

Program 2:

<?php

// opening a directory
$dir_handle = opendir("user/gfg/");

if(is_resource($dir_handle))
{

// reading the contents of the directory
while(($file_name = readdir($dir_handle)) !== false)
{
echo("File Name: " . $file_name);
echo "<br>" ;
}

// closing the directory
closedir($dir_handle);
}
else
{
echo("Failed to Open.");
}
}
else
{
echo("Invalid Directory.");
}
?>

Output:

File Name: gfg.jpg
File Name: ..
File Name: article.pdf
File Name: .
File Name: article.txt

Reference : http://php.net/manual/en/function.readdir.php