file_get_contents
(PHP 4 >= 4.3.0, PHP 5)
file_get_contents — Reads entire file into a string
Description
$filename
[, bool $use_include_path = false
[, resource $context
[, int $offset = -1
[, int $maxlen
]]]] )
This function is similar to file(), except that
file_get_contents() returns the file in a
string, starting at the specified offset
up to maxlen bytes. On failure,
file_get_contents() will return FALSE.
file_get_contents() is the preferred way to read the contents of a file into a string. It will use memory mapping techniques if supported by your OS to enhance performance.
Note:
If you're opening a URI with special characters, such as spaces, you need to encode the URI with urlencode().
Parameters
-
filename -
Name of the file to read.
-
use_include_path -
Note:
As of PHP 5 the
FILE_USE_INCLUDE_PATHconstant can be used to trigger include path search. -
context -
A valid context resource created with stream_context_create(). If you don't need to use a custom context, you can skip this parameter by
NULL. -
offset -
The offset where the reading starts on the original stream.
Seeking (
offset) is not supported with remote files. Attempting to seek on non-local files may work with small offsets, but this is unpredictable because it works on the buffered stream. -
maxlen -
Maximum length of data read. The default is to read until end of file is reached. Note that this parameter is applied to the stream processed by the filters.
Return Values
The function returns the read data or FALSE on failure.
This function may
return Boolean FALSE, but may also return a non-Boolean value which
evaluates to FALSE. Please read the section on Booleans for more
information. Use the ===
operator for testing the return value of this
function.
Errors/Exceptions
An E_WARNING level error is generated if filename cannot be found, maxlength
is less than zero, or if seeking to the specified offset in the stream fails.
Examples
Example #1 Get and output the source of the homepage of a website
<?php
$homepage = file_get_contents('http://www.example.com/');
echo $homepage;
?>
Example #2 Searching within the include_path
<?php
// <= PHP 5
$file = file_get_contents('./people.txt', true);
// > PHP 5
$file = file_get_contents('./people.txt', FILE_USE_INCLUDE_PATH);
?>
Example #3 Reading a section of a file
<?php
// Read 14 characters starting from the 21st character
$section = file_get_contents('./people.txt', NULL, NULL, 20, 14);
var_dump($section);
?>
The above example will output something similar to:
string(14) "lle Bjori Ro"
Example #4 Using stream contexts
<?php
// Create a stream
$opts = array(
'http'=>array(
'method'=>"GET",
'header'=>"Accept-language: en\r\n" .
"Cookie: foo=bar\r\n"
)
);
$context = stream_context_create($opts);
// Open the file using the HTTP headers set above
$file = file_get_contents('http://www.example.com/', false, $context);
?>
Changelog
| Version | Description |
|---|---|
| 5.1.0 |
Added the offset and
maxlen parameters.
|
| 5.0.0 | Added context support. |
Notes
Note: This function is binary-safe.
A URL can be used as a filename with this function if the fopen wrappers have been enabled. See fopen() for more details on how to specify the filename. See the Supported Protocols and Wrappers for links to information about what abilities the various wrappers have, notes on their usage, and information on any predefined variables they may provide.
When using SSL, Microsoft IIS will violate the protocol by closing the connection without sending a close_notify indicator. PHP will report this as "SSL: Fatal Protocol Error" when you reach the end of the data. To work around this, the value of error_reporting should be lowered to a level that does not include warnings. PHP 4.3.7 and higher can detect buggy IIS server software when you open the stream using the https:// wrapper and will suppress the warning. When using fsockopen() to create an ssl:// socket, the developer is responsible for detecting and suppressing this warning.
See Also
- file() - Reads entire file into an array
- fgets() - Gets line from file pointer
- fread() - Binary-safe file read
- readfile() - Outputs a file
- file_put_contents() - Write a string to a file
- stream_get_contents() - Reads remainder of a stream into a string
- stream_context_create() - Creates a stream context
- $http_response_header
- PHP Руководство
- Функции по категориям
- Индекс функций
- Справочник функций
- Расширения для работы с файловой системой
- Функции для работы с файловой системой
- basename
- chgrp
- chmod
- chown
- clearstatcache
- copy
- delete
- dirname
- disk_free_space
- disk_total_space
- diskfreespace
- fclose
- feof
- fflush
- fgetc
- fgetcsv
- fgets
- fgetss
- file_exists
- file_get_contents
- file_put_contents
- file
- fileatime
- filectime
- filegroup
- fileinode
- filemtime
- fileowner
- fileperms
- filesize
- filetype
- flock
- fnmatch
- fopen
- fpassthru
- fputcsv
- fputs
- fread
- fscanf
- fseek
- fstat
- ftell
- ftruncate
- fwrite
- glob
- is_dir
- is_executable
- is_file
- is_link
- is_readable
- is_uploaded_file
- is_writable
- is_writeable
- lchgrp
- lchown
- link
- linkinfo
- lstat
- mkdir
- move_uploaded_file
- parse_ini_file
- parse_ini_string
- pathinfo
- pclose
- popen
- readfile
- readlink
- realpath_cache_get
- realpath_cache_size
- realpath
- rename
- rewind
- rmdir
- set_file_buffer
- stat
- symlink
- tempnam
- tmpfile
- touch
- umask
- unlink
Коментарии
file_get_contents can do a POST, create a context for that first:
<?php
$opts = array('http' =>
array(
'method' => 'POST',
'header' => "Content-Type: text/xml\r\n".
"Authorization: Basic ".base64_encode("$https_user:$https_password")."\r\n",
'content' => $body,
'timeout' => 60
)
);
$context = stream_context_create($opts);
$url = 'https://'.$https_server;
$result = file_get_contents($url, false, $context, -1, 40000);
?>
There's barely a mention on this page but the $http_response_header will be populated with the HTTP headers if your file was a link. For example if you're expecting an image you can do this:
<?php
$data = file_get_contents('https://example.net/some-link');
$mimetype = null;
foreach ($http_response_header as $v) {
if (preg_match('/^content\-type:\s*(image\/[^;\s\n\r]+)/i', $v, $m)) {
$mimetype = $m[1];
}
}
if (!$mimetype) {
// not an image
}
Note that if an HTTP request fails but still has a response body, the result is still false, Not the response body which may have more details on why the request failed.To prevent mixed content most browsers/functions will use the protocol already used if you specify only // instead of http:// or https://. This is not the case with file_get_contents. You must specify the protocol.
This does not work:
<?php
$jsonData = file_get_contents('//example.com/file.json');
print $jsonData;
?>
Specifying only 'example.com/file.json' without the double slash does not work either.
When running on Apache 2.4 , using $_SERVER['REQUEST_SCHEME'] is a better way to be protocol agnostic.
<?php
$jsonData = file_get_contents($_SERVER['REQUEST_SCHEME'].'://example.com/file.json');
print $jsonData;
?>
If using another web server, you may have to get the protocol another way or hard code it.
If doing a negative offset to grab the end of a file and the file is shorter than the offset, then file_get_contents( ) will return false.
If you want it to just return what is available when the file is shorter than the negative offset, you could try again.
For example...
$contents = file_get_contents( $log_file, false, null, -4096 ); // Get last 4KB
if ( false === $contents ) {
// Maybe error, or maybe file less than 4KB in size.
$contents = file_get_contents( $log_file, false, null );
if ( false === $contents ) {
// Handle real error.
}
}