Reading Files in PHP: fread vs file_get_contents

This article explains two ways to read files in PHP: fread and file_get_contents , and discusses their similarities and differences.

1. Function syntax

fread ( resource $handle , int $length ) : string

$handle is a file pointer created by fopen() .

$length specifies the number of bytes to read.

The function returns a string of length $length.

file_get_contents ( string $filename , bool $include_path = false , resource $context = null , int $offset = -1 , int $maxlen = null ) : string

$filename is the path of the file to read.

$include_path determines whether to search in the include_path defined in php.ini .

$context allows stream context options; null ignores it.

$offset sets the start position (available since PHP 5.1).

$maxlen limits the number of bytes returned.

2. Differences

fread reads a specified number of bytes from a file handle, so you must manage the pointer and length; file_get_contents reads the entire file (or a portion defined by $offset/$maxlen) directly from the filename.

To read the whole file with fread , you can combine it with filesize() to obtain the file size.

Example using fread :

<?php
$filename = "./exit.txt";
$file = fopen($filename, 'r'); // use 'rb' for binary files
$file_info = fread($file, 10);
echo $file_info;
fclose($file);
?>

Output: php good b

Example using file_get_contents :

<?php
$filename = "./exit.txt";
echo file_get_contents($filename);
?>

Output: php good better Knowledge is power

Reading the entire file with fread and filesize() :

$file_info = fread($file, filesize($filename));