If you want to check if the function returned error, in case of a HTTP request an, it's not sufficient to test it against false. It may happen the return for that HTTP request was empty. In this case it's better to check if the return value is a bool.
<?php
$result=file_get_contents("http://www.example.com");
if ($result === false)
{
// treat error
} else {
// handle good case
}
?>
[EDIT BY thiago: Has enhacements from an anonymous user]
file_get_contents
(PHP 4 >= 4.3.0, PHP 5)
file_get_contents — ファイルの内容を全て文字列に読み込む
説明
この関数は file() と似ていますが、 offset で指定した場所から開始し maxlen バイト分だけ ファイルの内容を文字列に読み込むという点が異なります。 失敗した場合、file_get_contents() は FALSE を返します。
file_get_contents()はファイルの内容を文字列に読み込む 方法として好ましいものです。もしOSがサポートしていれば パフォーマンス向上のためにメモリマッピング技術が使用されます。
注意:
空白のような特殊な文字を有する URI をオープンする場合には、 urlencode() でその URI をエンコードする必要があります。
注意:
maxlen のデフォルト値は -1 ではありません。PHP の内部で使用する値で、 ファイル終端に達するまでストリーム全体をコピーするという意味を持つものとなります。 このデフォルト値を指定する唯一の方法は、パラメータリストからこのパラメータをはずすことです。
パラメータ
- filename
-
データを読み込みたいファイルの名前。
- use_include_path
-
注意:
PHP 5 以降では、FILE_USE_INCLUDE_PATH を使用して インクルードパス から探すことができます。
- context
-
stream_context_create() で作成したコンテキストリソース。 独自のコンテキストを使用する必要がない場合は、このパラメータに NULL を指定します。
- offset
-
元のストリーム上で、読み込みを開始するオフセット位置。
- maxlen
-
読み込むデータの最大バイト数。 デフォルトは、ファイル終端に達するまで読み込みます。 このパラメータは、フィルタが処理した後のストリームに適用されることに注意しましょう。
返り値
読み込んだデータを返します。失敗した場合に FALSE を返します。
例
例1 とあるウェブサイトのホームページのソースの取得と出力
<?php
$homepage = file_get_contents('http://www.example.com/');
echo $homepage;
?>
例2 include_path の検索
<?php
// <= PHP 5
$file = file_get_contents('./people.txt', true);
// > PHP 5
$file = file_get_contents('./people.txt', FILE_USE_INCLUDE_PATH);
?>
例3 ファイルの一部の読み込み
<?php
// 21 文字目から 14 文字ぶん読み込みます
$section = file_get_contents('./people.txt', NULL, NULL, 20, 14);
var_dump($section);
?>
上の例の出力は、 たとえば以下のようになります。
string(14) "lle Bjori Ro"
例4 ストリームコンテキストの使用
<?php
// ストリームを作成します
$opts = array(
'http'=>array(
'method'=>"GET",
'header'=>"Accept-language: en\r\n" .
"Cookie: foo=bar\r\n"
)
);
$context = stream_context_create($opts);
// 上で設定した HTTP ヘッダを使用してファイルをオープンします
$file = file_get_contents('http://www.example.com/', false, $context);
?>
変更履歴
| バージョン | 説明 |
|---|---|
| 5.1.0 | offset と maxlen パラメータが追加されました。 |
| 5.0.0 | コンテキストサポートが追加されました。 |
注意
注意: この関数はバイナリデータに対応しています。
fopen wrappers が有効の場合、この関数のファイル名として URL を使用することができます。ファイル名の指定方法に関する詳細は fopen() を参照ください。 サポートするプロトコル/ラッパー には、さまざまなラッパーの機能やその使用法、 提供される定義済み変数などの情報がまとめられています。
IIS のような、いくつかの標準に 対応してない Web サーバは、PHP に警告を発生させるような手順でデータを送信します。 このようなサーバを使用する場合は、 error_reporting を警告を発生しないレベルまで小さくする必要があります。 PHP 4.3.7 以降では、https:// ラッパーでストリームをオープンする際に バグがある IIS サーバソフトウエアを検出することができ、この警告を抑制することができます。 あなたが ssl:// ソケットを作成するために fsockopen() を使用している場合、 自らこの警告を検出し、抑制する必要があります。
参考
- file() - ファイル全体を読み込んで配列に格納する
- fgets() - ファイルポインタから 1 行取得する
- fread() - バイナリセーフなファイルの読み込み
- readfile() - ファイルを出力する
- file_put_contents() - 文字列をファイルに書き込む
- stream_get_contents() - 残りのストリームを文字列に読み込む
- stream_context_create() - ストリームコンテキストを作成する
- $http_response_header
file_get_contents
27-Mar-2010 10:03
14-Jan-2010 02:22
Sometimes you might get an error opening an http URL.
even though you have set "allow_url_fopen = On" in php.ini
For me the the solution was to also set "user_agent" to something.
28-Oct-2009 01:00
On Centos 5, and maybe other Red Hat based systems, any attempt to use file_get_contents to access a URL on an http port other than 80 (e.g. "http://www.example.com:8040/page") may fail with a permissions violation (error 13) unless the box you are running php on has its seLinux set to 'permissive' not 'enforcing' . Otherwise the request doesn't even get out of the box, i.e. the permissions violation is generated locally by seLinux.
09-Jun-2009 09:35
In my dev environment with a relatively low-speed drive (standard SATA 7200RPM) reading a 25MB zip file in 10 times...
<?php
$data = `cat /tmp/test.zip`;
// 1.05 seconds
$fh = fopen('/tmp/test.zip', 'r');
$data = fread($fh, filesize('/tmp/test.zip'));
fclose($fh);
// 1.31 seconds
$data = file_get_contents('/tmp/test.zip');
// 1.33 seconds
?>
However, on a 21k text file running 100 iterations...
<?php
$data = `cat /tmp/test.txt`;
// 1.98 seconds
$fh = fopen('/tmp/test.txt', 'r');
$data = fread($fh, filesize('/tmp/test.txt'));
fclose($fh);
// 0.00082 seconds
$data = file_get_contents('/tmp/test.txt');
// 0.0069 seconds
?>
Despite the comment about file_get_contents being faster do to memory mapping, file_get_contents is slowest in both of the above examples. If you need the best performance out of your production box, you might want to throw together a script to check out which method is fastest for what size files on that particular machine, then optimize your code to check the file size and use the appropriate function for it.
10-Aug-2008 09:34
A UTF-8 issue I've encountered is that of reading a URL with a non-UTF-8 encoding that is later displayed improperly since file_get_contents() related to it as UTF-8. This small function should show you how to address this issue:
<?php
function file_get_contents_utf8($fn) {
$content = file_get_contents($fn);
return mb_convert_encoding($content, 'UTF-8',
mb_detect_encoding($content, 'UTF-8, ISO-8859-1', true));
}
?>
07-Aug-2008 12:34
if $filename has a relative path file_get_contents returns the uninterpreted sourcecode of the php-file with all comments etc.
I don't know whether this is a bug or intented or caused by server-configuration.
I think this behaviour should be included in the description of the function.
05-Aug-2008 11:13
I recently upgraded my server to Slackware 12.0.
After this, a program of mine stopped working: the call to file_get_contents (to an URL served by a custom HTTP server) was returning false without generating any error!
After some investigations I saw this: my custom HTTP server closes the connection at the end of the content. This (without the header "Connection: close") seems to cause the problem I described.
To solve the problem I simply added that header to the answer of my custom HTTP server.
19-Jul-2008 12:17
if( false == ($str=file_get_contents( '../relative_path/test.txt' )))
echo "Could not read file.";
else
echo "File contents: $str";
# Note: if the file cannot be opened then file_get_contents will attempt to warn the following:
# Warning: file_get_contents(filename): failed to open stream
http://www.codesplunk.com/nr/questions/php1.html
15-Apr-2008 09:38
Setting the timeout properly without messing with ini values:
<?php
$ctx = stream_context_create(array(
'http' => array(
'timeout' => 1
)
)
);
file_get_contents("http://example.com/", 0, $ctx);
?>
02-Apr-2008 09:12
This is a nice and simple substitute to get_file_contents() using curl, it returns FALSE if $contents is empty.
<?php
function curl_get_file_contents($URL)
{
$c = curl_init();
curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($c, CURLOPT_URL, $URL);
$contents = curl_exec($c);
curl_close($c);
if ($contents) return $contents;
else return FALSE;
}
?>
Hope this help, if there is something wrong or something you don't understand let me know :)
29-Jan-2008 07:29
<?PHP
//PHP 4.2.x Compatibility function
if (!function_exists('file_get_contents')) {
function file_get_contents($filename, $incpath = false, $resource_context = null)
{
if (false === $fh = fopen($filename, 'rb', $incpath)) {
trigger_error('file_get_contents() failed to open stream: No such file or directory', E_USER_WARNING);
return false;
}
clearstatcache();
if ($fsize = @filesize($filename)) {
$data = fread($fh, $fsize);
} else {
$data = '';
while (!feof($fh)) {
$data .= fread($fh, 8192);
}
}
fclose($fh);
return $data;
}
}
?>
15-Jan-2008 11:58
I decided to make a similar function to this, called file_post_contents, it uses POST instead of GET to call, kinda handy...
<?php
function file_post_contents($url,$headers=false) {
$url = parse_url($url);
if (!isset($url['port'])) {
if ($url['scheme'] == 'http') { $url['port']=80; }
elseif ($url['scheme'] == 'https') { $url['port']=443; }
}
$url['query']=isset($url['query'])?$url['query']:'';
$url['protocol']=$url['scheme'].'://';
$eol="\r\n";
$headers = "POST ".$url['protocol'].$url['host'].$url['path']." HTTP/1.0".$eol.
"Host: ".$url['host'].$eol.
"Referer: ".$url['protocol'].$url['host'].$url['path'].$eol.
"Content-Type: application/x-www-form-urlencoded".$eol.
"Content-Length: ".strlen($url['query']).$eol.
$eol.$url['query'];
$fp = fsockopen($url['host'], $url['port'], $errno, $errstr, 30);
if($fp) {
fputs($fp, $headers);
$result = '';
while(!feof($fp)) { $result .= fgets($fp, 128); }
fclose($fp);
if (!$headers) {
//removes headers
$pattern="/^.*\r\n\r\n/s";
$result=preg_replace($pattern,'',$result);
}
return $result;
}
}
?>
03-Dec-2007 04:56
Seems file looks for the file inside the current working (executing) directory before looking in the include path, even with the FILE_USE_INCLUDE_PATH flag specified.
Same behavior as include actually.
By the way I feel the doc is not entirely clear on the exact order of inclusion (see include). It seems to say the include_path is the first location to be searched, but I have come across at least one case where the directory containing the file including was actually the first to be searched.
Drat.
11-Jul-2007 09:38
If you're having problems with binary and hex data:
I had a problem when trying to read information from a ttf, which is primarily hex data. A binary-safe file read automatically replaces byte values with their corresponding ASCII characters, so I thought that I could use the binary string when I needed readable ASCII strings, and bin2hex() when I needed hex strings.
However, this became a problem when I tried to pass those ASCII strings into other functions (namely gd functions). var_dump showed that a 5-character string contained 10 characters, but they weren't visible. A binary-to-"normal" string conversion function didn't seem to exist and I didn't want to have to convert every single character in hex using chr().
I used unpack with "c*" as the format flag to see what was going on, and found that every other character was null data (ordinal 0). To solve it, I just did
str_replace(chr(0), "", $string);
which did the trick.
This took forever to figure out so I hope this helps people reading from hex data!
02-May-2007 04:26
you'll find the http response headers in: $http_response_header
;o)
17-Apr-2007 04:37
[Editors note: As of PHP 5.2.1 you can specify `timeout` context option and pass the context to file_get_contents()]
The only way I could get get_file_contents() to wait for a very slow http request was to set the socket timeout as follows.
ini_set('default_socket_timeout', 120);
$a = file_get_contents("http://abcxyz.com");
Other times like execution time and input time had no effect.
05-Dec-2006 08:52
Use the previous example if you want to request the server for a special part of the content, IF and only if the server accepts the method.
If you want a simple example to ask the server for all the content, but only save a portion of it, do it this way:
<?
$content=file_get_contents("http://www.google.com",FALSE,NULL,0,20);
echo $content;
?>
This will echo the 20 first bytes of the google.com source code.
04-Aug-2006 08:55
the bug #36857 was fixed.
http://bugs.php.net/36857
Now you may use this code,to fetch the partial content like this:
<?php
$context=array('http' => array ('header'=> 'Range: bytes=1024-', ),);
$xcontext = stream_context_create($context);
$str=file_get_contents("http://www.fcicq.net/wp/",FALSE,$xcontext);
?>
that's all.
15-Nov-2005 10:47
If, like me, you are on a Microsoft network with ISA server and require NTLM authentication, certain applications will not get out of the network. SETI@Home Classic and PHP are just 2 of them.
The workaround is fairly simple.
First you need to use an NTLM Authentication Proxy Server. There is one written in Python and is available from http://apserver.sourceforge.net/. You will need Python from http://www.python.org/.
Both sites include excellent documentation.
Python works a bit like PHP. Human readable code is handled without having to produce a compiled version. You DO have the opportunity of compiling the code (from a .py file to a .pyc file).
Once compiled, I installed this as a service (instsrv and srvany - parts of the Windows Resource Kit), so when the server is turned on (not logged in), the Python based NTLM Authentication Proxy Server is running.
Then, and here is the bit I'm really interested in, you need to tell PHP you intend to route http/ftp requests through the NTLM APS.
To do this, you use contexts.
Here is an example.
<?php
// Define a context for HTTP.
$aContext = array(
'http' => array(
'proxy' => 'tcp://127.0.0.1:8080', // This needs to be the server and the port of the NTLM Authentication Proxy Server.
'request_fulluri' => True,
),
);
$cxContext = stream_context_create($aContext);
// Now all file stream functions can use this context.
$sFile = file_get_contents("http://www.php.net", False, $cxContext);
echo $sFile;
?>
Hopefully this helps SOMEONE!!!
31-Jan-2005 07:23
This functionality is now implemented in the PEAR package PHP_Compat.
More information about using this function without upgrading your version of PHP can be found on the below link:
http://pear.php.net/package/PHP_Compat
