Filesystem 函数
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PHP手册

file

(PHP 4, PHP 5)

file把整个文件读入一个数组中

说明

array file ( string $filename [, int $use_include_path [, resource $context ]] )

file_get_contents() 一样,只除了 file() 将文件作为一个数组返回。数组中的每个单元都是文件中相应的一行,包括换行符在内。如果失败 file() 返回 FALSE

如果也想在 include_path 中搜寻文件的话,可以将可选参数 use_include_path 设为 "1"。

<?php
// 将一个文件读入数组。本例中通过 HTTP 从 URL 中取得 HTML 源文件。
$lines file('http://www.example.com/');
// 在数组中循环,显示 HTML 的源文件并加上行号。
foreach ($lines as $line_num => $line) {
    echo 
"Line #<b>{$line_num}</b> : " htmlspecialchars($line) . "<br />\n";
}
// 另一个例子将 web 页面读入字符串。参见 file_get_contents()。
$html implode(''file ('http://www.example.com/'));
?>
Tip

如已启用fopen 包装器,在此函数中, URL 可作为文件名。关于如何指定文件名详见 fopen()。各种 wapper 的不同功能请参见 Supported Protocols and Wrappers,注意其用法及其可提供的预定义变量。

Note:

返回的数组中每一行都包括了行结束符,因此如果不需要行结束符时还需要使用 rtrim() 函数。

Note: 在读取在 Macintosh 电脑中或由其创建的文件时, 如果 PHP 不能正确的识别行结束符,启用运行时配置可选项 auto_detect_line_endings 也许可以解决此问题。

Note:

从 PHP 4.3.0 开始可以用 file_get_contents() 来将文件读入到一个字符串返回。

从 PHP 4.3.0 开始 file() 可以安全用于二进制文件。

Note: 在 PHP 5.0.0 中增加了 对上下文(Context)的支持。 有关 上下文(Context) 的说明参见 Streams

Warning

使用 SSL 时,Microsoft IIS 会违反协议不发送close_notify标记就关闭连接。PHP 会在到达数据尾端时报告“SSL: Fatal Protocol Error”。 要解决此问题,error_reporting 应设定为降低级别至不包含警告。 PHP 4.3.7 及更高版本可以在使用 https:// 包装器打开流时检测出有问题的 IIS 服务器软件 并抑制警告。在使用 fsockopen() 创建 ssl:// 套接字时, 开发者需检测并抑制此警告。

参见 readfile()fopen()fsockopen()popen()file_get_contents()include()

参数

filename

Path to the file.

Tip

如已启用fopen 包装器,在此函数中, URL 可作为文件名。关于如何指定文件名详见 fopen()。各种 wapper 的不同功能请参见 Supported Protocols and Wrappers,注意其用法及其可提供的预定义变量。

flags

The optional parameter flags can be one, or more, of the following constants:

FILE_USE_INCLUDE_PATH
Search for the file in the include_path.
FILE_IGNORE_NEW_LINES
Do not add newline at the end of each array element
FILE_SKIP_EMPTY_LINES
Skip empty lines

context

A context resource created with the stream_context_create() function.

Note: 在 PHP 5.0.0 中增加了 对上下文(Context)的支持。 有关 上下文(Context) 的说明参见 Streams

返回值

Returns the file in an array. Each element of the array corresponds to a line in the file, with the newline still attached. Upon failure, file() returns FALSE.

Note:

Each line in the resulting array will include the line ending, unless FILE_IGNORE_NEW_LINES is used, so you still need to use rtrim() if you do not want the line ending present.

Note: 在读取在 Macintosh 电脑中或由其创建的文件时, 如果 PHP 不能正确的识别行结束符,启用运行时配置可选项 auto_detect_line_endings 也许可以解决此问题。

更新日志

版本 说明
5.0.0 The context parameter was added
5.0.0 Prior to PHP 5.0.0 the flags parameter only covered include_path and was enabled with 1
4.3.0 file() became binary safe

范例

Example #1 file() example

<?php
// Get a file into an array.  In this example we'll go through HTTP to get
// the HTML source of a URL.
$lines file('http://www.example.com/');

// Loop through our array, show HTML source as HTML source; and line numbers too.
foreach ($lines as $line_num => $line) {
    echo 
"Line #<b>{$line_num}</b> : " htmlspecialchars($line) . "<br />\n";
}

// Another example, let's get a web page into a string.  See also file_get_contents().
$html implode(''file('http://www.example.com/'));

// Using the optional flags parameter since PHP 5
$trimmed file('somefile.txt'FILE_IGNORE_NEW_LINES FILE_SKIP_EMPTY_LINES);
?>

注释

Warning

使用 SSL 时,Microsoft IIS 会违反协议不发送close_notify标记就关闭连接。PHP 会在到达数据尾端时报告“SSL: Fatal Protocol Error”。 要解决此问题,error_reporting 应设定为降低级别至不包含警告。 PHP 4.3.7 及更高版本可以在使用 https:// 包装器打开流时检测出有问题的 IIS 服务器软件 并抑制警告。在使用 fsockopen() 创建 ssl:// 套接字时, 开发者需检测并抑制此警告。

参见


Filesystem 函数
在线手册:中文 英文
PHP手册
PHP手册 - N: 把整个文件读入一个数组中

用户评论:

twichi at web dot de (13-Sep-2011 08:33)

read from CSV data (file) into an array with named keys

... with or without 1st row = header (keys)
(see 4th parameter of function call as  true / false)

<?php
// --------------------------------------------------------------

function csv_in_array($url,$delm=";",$encl="\"",$head=false) {
   
   
$csvxrow = file($url);   // ---- csv rows to array ----
   
   
$csvxrow[0] = chop($csvxrow[0]);
   
$csvxrow[0] = str_replace($encl,'',$csvxrow[0]);
   
$keydata = explode($delm,$csvxrow[0]);
   
$keynumb = count($keydata);
   
    if (
$head === true) {
   
$anzdata = count($csvxrow);
   
$z=0;
    for(
$x=1; $x<$anzdata; $x++) {
       
$csvxrow[$x] = chop($csvxrow[$x]);
       
$csvxrow[$x] = str_replace($encl,'',$csvxrow[$x]);
       
$csv_data[$x] = explode($delm,$csvxrow[$x]);
       
$i=0;
        foreach(
$keydata as $key) {
           
$out[$z][$key] = $csv_data[$x][$i];
           
$i++;
            }   
       
$z++;
        }
    }
    else {
       
$i=0;
        foreach(
$csvxrow as $item) {
           
$item = chop($item);
           
$item = str_replace($encl,'',$item);
           
$csv_data = explode($delm,$item);
            for (
$y=0; $y<$keynumb; $y++) {
              
$out[$i][$y] = $csv_data[$y];
            }
       
$i++;
        }
    }

return
$out;
}

// --------------------------------------------------------------

?>

fuction call with 4 parameters:

(1) = the file with CSV data (url / string)
(2) = colum delimiter (e.g: ; or | or , ...)
(3) = values enclosed by (e.g: ' or " or ^ or ...)
(4) = with or without 1st row = head (true/false)

<?php

// ----- call ------
$csvdata = csv_in_array( $yourcsvfile, ";", "\"", true );
// -----------------

// ----- view ------
echo "<pre>\r\n";
print_r($csvdata);
echo
"</pre>\r\n";
// -----------------

?>

PS: also see: http://php.net/manual/de/function.fgetcsv.php to read CSV data into an array
... and other file-handling methods

^

marios88 at gmail dot com (06-Feb-2010 10:59)

Quick and easy way to reverse read a file without array_reverse

<?php
$myfile
= 'test.txt';
$lines = file($myfile);   
for(
$i=count($lines);$i>0;$i--){
    echo
$lines[$i];
}
?>

d basin (14-Oct-2009 11:47)

this may be obvious, but it took me a while to figure out what I was doing wrong. So I wanted to share. I have a file on my "c:\" drive. How do I file() it?

Don't forget the backslash is special and you have to "escape" the backslash i.e. "\\":

<?php

$lines
= file("C:\\Documents and Settings\\myfile.txt");

foreach(
$lines as $line)
{
    echo(
$line);
}

?>

hope this helps...

PenguinMan98 at usa dot net (21-Apr-2008 11:49)

on file() and flock()

My supervisor came up with a brilliant plan to workaround the inability of the file() to work on a flock()'ed file.

We created a dummy file called lockfile.txt.  We would flock() lockfile.txt.  Once we had a lock on it, we used file() on the file we wanted to read, then altered the file and called fclose on both files.

jon+spamcheck at phpsitesolutions dot com (16-Apr-2008 09:03)

A user suggested using rtrim always, due to the line ending conflict with files that have an EOL that differs from the server EOL.

Using rtrim with it's default character replacement is a bad solution though, as it removes all whitespace in addition to the '\r' and '\n' characters.

A good solution using rtrim follows:

<?php
$line
= rtrim($line, "\r\n") . PHP_EOL;
?>

This removes only EOL characters, and replaces with the server's EOL character, thus making preg_* work fine when matching the EOL ($)

vbchris at gmail dot com (16-Feb-2008 09:15)

If you're getting "failed to open stream: Permission denied" when trying to use either file() or fopen() to access files on another server. Check your host doesn't have any firewall restrictions in-place which prevent outbound connections. This is the case with my host Aplus.net

Reversed: moc dot liamg at senroc dot werdna (12-Jul-2007 10:25)

This note applies to PHP 5.1.6 under Windows (although may apply to other versions).

It appears that the 'FILE_IGNORE_NEW_LINES' flag doesn't remove newlines properly when reading Windows-style text files, i.e. files whose lines end in '\r\n'.

Solution: Always use 'rtrim()' in preference to 'FILE_IGNORE_NEW_LINES'.

info at carstanje dot com (28-Nov-2006 08:33)

Using file() for reading large text files > 10 Mb gives problems, therefore you should use this instead. It is much slower but it works fine. $lines will return an array with all the lines.

<?php
$handle
= @fopen('yourfile...', "r");
if (
$handle) {
   while (!
feof($handle)) {
      
$lines[] = fgets($handle, 4096);
   }
  
fclose($handle);
}
?>

richardtcunningham at gmail dot com (11-Jul-2006 10:19)

justin at visunet dot ie's note of 20-Mar-2003 states
"Note: Now that file() is binary safe it is 'much' slower than it used to be. If you are planning to read large files it may be worth your while using fgets() instead of file()."

I tested fgets(), file_get_contents(), and file() on PHP 4.3.2 and PHP 5 and timed each to be under a second with over 200,000 lines. I do not know if he was testing extremely long lines or what, but I could not duplicate the difference that he mentioned.

jonathan dot gotti at free dot fr (01-Feb-2006 10:52)

you can use
$file = array_map('rtrim',file('myfile.txt'));
to remove annoying ending lines of the resulting array.

Nuts (18-Jan-2006 11:16)

WARNING ON WINDOWS:
file() function will add "\r\n" in to the end of the row, even if you use only "\n" char to make rows in the file!

On UNIX systems there is no such problem.

dir @ badblue com (12-Sep-2003 10:48)

Jeff's array2file function is a good start; here are a couple of improvements (no possibility of handle leak when fwrite fails, additional capability of both string2file and array2file; presumably faster performance through use of implode).

<?php
function String2File($sIn, $sFileOut) {
 
$rc = false;
  do {
    if (!(
$f = fopen($sFileOut, "wa+"))) {
     
$rc = 1; break;
    }
    if (!
fwrite($f, $sIn)) {
     
$rc = 2; break;
    }
   
$rc = true;
  } while (
0);
  if (
$f) {
   
fclose($f);
  }
  return (
$rc);
}

function
Array2File($aIn, $sFileOut) {
  return (
String2File(implode("\n", $aIn), $sFileOut));
}
?>

If you're generating your string text using a GET or POST from a TEXTAREA (e.g., a mini-web-text-editor), remember that strip_slashes and str_replace of "/r/n" to "/n" may be necessary as well using these functions.

HTH --dir @ badblue com

John (21-Jul-2003 12:32)

after many months of confusion and frustration, i have finally figured out something that i should have noticed the first time around.

you can't file("test.txt") when that same file has been flocked. i guess i didn't have a full understanding of what i was doing when i used flock(). all i had to do was move the flock() around, and all was well.

justin at visunet dot ie (20-Mar-2003 05:36)

Note: Now that file() is binary safe it is 'much' slower than it used to be. If you are planning to read large files it may be worth your while using fgets() instead of file() For example:

<?php
$fd
= fopen ("log_file.txt", "r");
while (!
feof ($fd))
{
  
$buffer = fgets($fd, 4096);
  
$lines[] = $buffer;
}
fclose ($fd);
?>

The resulting array is $lines.

I did a test on a 200,000 line file. It took seconds with fgets()  compared to minutes with file().

andrea at brancatelli dot it (16-Mar-2002 07:16)

file() has a strange behaviour when reading file with both \n and \r as line delimitator (DOS files), since it will return an array with every single line but with just a \n in the end. It seems like \r just disappears.

This is happening with PHP 4.0.4 for OS/2. Don't know about the Windows version.

php@don't_spam_me (09-Feb-2002 08:56)

It appears that the file() function causes file access problems for perl cgi scripts accessing the same files.  I am using Perl v5.6.0 in linux with PHP/4.0.4pl1.  After running a php app using the file() function, any perl cgi trying to access the same file randomly dies returning an internal server error: premature end of script headers.

The simple fix is to use fopen(), fgets() and fclose() instead of file().