Php получения файла по ссылке

file_get_contents

This function is similar to file() , except that file_get_contents() returns the file in a string , starting at the specified offset up to length 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

Note:

The FILE_USE_INCLUDE_PATH constant can be used to trigger include path search. This is not possible if strict typing is enabled, since FILE_USE_INCLUDE_PATH is an int . Use true instead.

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 .

The offset where the reading starts on the original stream. Negative offsets count from the end of the 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.

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, length is less than zero, or if seeking to the specified offset in the stream fails.

When file_get_contents() is called on a directory, an E_WARNING level error is generated on Windows, and as of PHP 7.4 on other operating systems as well.

Changelog

Version	Description
8.0.0	length is nullable now.
7.1.0	Support for negative offset s has been added.

Examples

Example #1 Get and output the source of the homepage of a website

Example #2 Searching within the include_path

// If strict types are enabled i.e. declare(strict_types=1);
$file = file_get_contents ( ‘./people.txt’ , true );
// Otherwise
$file = file_get_contents ( ‘./people.txt’ , FILE_USE_INCLUDE_PATH );
?>

Example #3 Reading a section of a file

// Read 14 characters starting from the 21st character
$section = file_get_contents ( ‘./people.txt’ , FALSE , NULL , 20 , 14 );
var_dump ( $section );
?>

The above example will output something similar to:

Example #4 Using stream contexts

// 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 );
?>

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 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 data to a file
• stream_get_contents() — Reads remainder of a stream into a string
• stream_context_create() — Creates a stream context
• $http_response_header

User Contributed Notes 6 notes

file_get_contents can do a POST, create a context for that first:

$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 );

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.

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:

$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
>

if the connection is
content-encoding: gzip
and you need to manually ungzip it, this is apparently the key
$c=gzinflate( substr($c,10,-8) );
(stolen from the net)

//从指定位置获取指定长度的文件内容
function file_start_length($path,$start=0,$length=null) if(!file_exists($path)) return false;
$size=filesize($path);
if($start <0) $start+=$size;
if($length===null) $length=$size-$start;
return file_get_contents($path, false, null, $start, $length );
>

I’m not sure why @jlh was downvoted, but I verified what he reported.

>>> file_get_contents($path false, null, 5, null)
=> «»
>>> file_get_contents($path, false, null, 5, 5)
=> «r/bin»

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How to Download a File in PHP

Generally, no PHP script is required to download a file with the extensions exe and zip. If the file location of this type of file is set in the href attribute of the anchor element, then the file automatically downloads when the user clicks on the download link. Some files, such as image files, PDF files, text files, CSV files, etc., do not download automatically, and instead, open in the browser when the user clicks on the download link. These files can be downloaded forcibly in PHP using the readfile() function that does not download automatically. This tutorial shows you how to forcibly download any file using PHP script.

Check Download Links

It was previously mentioned that zip and exe files download automatically, without using PHP script. First, create an HTML file with the following code. Here, the four anchor elements are defined to download the four types of files. These file types include TEXT, ZIP, PDF, and JPG files.

Download.html

Output
The following dialog box will appear to download the file after clicking the zip file link. The user can then download the file or open the file in the archive manager.

If you click on the image file, the image will be opened automatically in the browser, as shown in the following output. You must save the file to make a copy of the image file in the local drive. In the same way, when you click on PDF and TEXT file links, the content of the file will be opened in the browser without downloading the file. The solution to this problem is to download the file forcibly using the built-in PHP readfile() function.

Download File Using readfile() Function

The readfile() function is used in PHP script to forcibly download any file of the current location, or the file with the file path. The syntax of this function is given below.

Syntax
int readfile ( string $filename [, bool $use_include_path = false [, resource $context ]] )

This function can take three arguments. The first argument is mandatory, and the other two arguments are optional. The first argument, $filename, stores the filename or filename with the path that will download. The default value of the second parameter, $use_include_path, is false and will be set to true if the filename with the path is used in the first argument. The third argument, $context, is used to indicate the context stream resource. This function returns the number of bytes read from the file mentioned in the first argument. The uses of this function are shown in the following two examples.

Example 1: Download File with Filename

In this example, we will create an HTML file with the following code, where the file name will be passed as a parameter of the URL named path, and the value of this parameter will be passed to the PHP file named download.php.

download2.html

We will create the PHP file with the following code to download the file forcibly. Here, the isset() function is used to check whether the $_GET[‘path’] is defined. If the variable is defined, the file_exists() function is used to check whether the file exists in the server. Next, the header() function is used to set the necessary header information before using the readfile() function. The basename() function is used to retrieve the filename, and the filesize() function is used to read the size of the file in bytes, which will be shown in the opening dialog box to download the file. The flush() function is used to clear the output buffer. The readfile() function is used with the filename only, here.

download.php

if ( isset ( $_GET [ ‘path’ ] ) )
{
//Read the filename
$filename = $_GET [ ‘path’ ] ;
//Check the file exists or not
if ( file_exists ( $filename ) ) {

//Define header information
header ( ‘Content-Description: File Transfer’ ) ;
header ( ‘Content-Type: application/octet-stream’ ) ;
header ( «Cache-Control: no-cache, must-revalidate» ) ;
header ( «Expires: 0» ) ;
header ( ‘Content-Disposition: attachment; filename=»‘ . basename ( $filename ) . ‘»‘ ) ;
header ( ‘Content-Length: ‘ . filesize ( $filename ) ) ;
header ( ‘Pragma: public’ ) ;

//Clear system output buffer
flush ( ) ;

//Read the size of the file
readfile ( $filename ) ;

//Terminate from the script
die ( ) ;
}
else {
echo «File does not exist.» ;
}
}
else
echo «Filename is not defined.»
?>

Output
The following output will appear after clicking the download link of the image file. The file size of the rose.jpg image is 27.2 KB, as shown in the dialog box. You can download the file by selecting the Save File radio button and pressing the OK button.

Example 2: Download File with File Path

If the file exists at the given file location, the file path will be required to mention in the URL. In this example, we will create an HTML file with the following code, which will pass the filename with the file path:

download3.html

We will create a PHP file with the following code to download a file from the file path. The PHP code in the previous example will be slightly modified to download the file from the given path. The clearstatecache() function is used to clear the cache that was previously stored. Two arguments are used in the readfile() function.

download2.php

if ( isset ( $_GET [ ‘path’ ] ) )
{
//Read the url
$url = $_GET [ ‘path’ ] ;

//Check the file path exists or not
if ( file_exists ( $url ) ) {

//Define header information
header ( ‘Content-Description: File Transfer’ ) ;
header ( ‘Content-Type: application/octet-stream’ ) ;
header ( ‘Content-Disposition: attachment; filename=»‘ . basename ( $url ) . ‘»‘ ) ;
header ( ‘Content-Length: ‘ . filesize ( $url ) ) ;
header ( ‘Pragma: public’ ) ;

//Clear system output buffer
flush ( ) ;

//Read the size of the file
readfile ( $url , true ) ;

//Terminate from the script
die ( ) ;
}
else {
echo «File path does not exist.» ;
}
}
echo «File path is not defined.»

Output
After the download link of the PDF file is clicked, the following output will appear.

Video Tutorial

Conclusion

This article provided a simple way to forcibly download any file using the PHP script, to help readers to add the download feature in their script.

About the author

Fahmida Yesmin

I am a trainer of web programming courses. I like to write article or tutorial on various IT topics. I have a YouTube channel where many types of tutorials based on Ubuntu, Windows, Word, Excel, WordPress, Magento, Laravel etc. are published: Tutorials4u Help.

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