Using PHP file_exists() to Check File and Directory Existence

In PHP programming, checking whether a file or directory exists is a common task, and the file_exists() function is used for this purpose.

Syntax:

bool file_exists ( string $filename )

Parameter:

$filename : the path of the file or directory to check.

Return value: Returns true if the file or directory exists, otherwise false .

Example: The following example demonstrates how to use file_exists() to check a file and a directory.

<?php
// Check if a file exists
$file = 'example.txt';
if (file_exists($file)) {
echo "File exists.";
} else {
echo "File does not exist.";
}
// Check if a directory exists
$dir = 'example_dir';
if (file_exists($dir) && is_dir($dir)) {
echo "Directory exists.";
} else {
echo "Directory does not exist.";
}
?>

The script first defines a file path variable $file and uses file_exists() to determine its existence, outputting an appropriate message. It then defines a directory path variable $dir and checks both existence and that it is a directory using file_exists() together with is_dir() .

Notes:

The function can also check remote files by providing a URL.

It does not differentiate between files and directories; a directory will also return true .

It only reports existence and does not consider accessibility permissions.

It is advisable to use is_readable() or is_writable() before accessing the file to avoid permission errors.

Conclusion: The file_exists() function is essential for verifying the presence of files or directories in PHP, enabling developers to write safe conditional logic for file handling.