Working with Files and Directories in PHP

PHP provides straightforward functions to read data from files and write data to them. Let’s start with an example of reading data from a file:

<?php
$file = ‘example.txt’;
$content = file_get_contents($file);
echo $content;
?>
To write data to a file, you can use the file_put_contents() function:

<?php
$file = ‘example.txt’;
$content = “Hello, PHP!”;
file_put_contents($file, $content);
?>

File permissions are essential for controlling access to files and directories, ensuring that sensitive data remains secure. In PHP, you can set file permissions using the chmod() function. For example, to give read, write, and execute permissions to the owner of a file:

<?php
$file = ‘example.txt’;
chmod($file, 0644); // Owner: read and write, Group: read, Others: read
?>

PHP offers a wealth of filesystem functions to handle various file and directory operations. Some essential functions include:

<?php
$file = ‘example.txt’;
if (file_exists($file) && is_file($file)) {
echo “File exists!”;
}

$dir = ‘my_directory’;
if (!is_dir($dir)) {
mkdir($dir);
}
?>