Chapter 6 PHP Directory and File Operation_PHP Tutorial-PHP Tutorial-php.cn

one. Directory operations
basename -- Returns the file name part of the path
dirname -- Returns the directory part of the path
pathinfo -- Returns file path information
realpath -- Returns the normalized absolute path name

Copy code The code is as follows:

 
$path = 'demo1.php'; 
$path = realpath($path); 
echo basename($path); 
echo '
'; 
echo dirname($path); 
echo '
 '; 
$array_path = pathinfo($path); 
echo 'basename : '.$array_path['basename'].'
'; 
echo 'dirname : '.$array_path[ 'dirname'].'
'; 
echo 'extension : '.$array_path['extension'].'
'; 
echo 'filename : '.$array_path['filename '].'
'; 
?> 

Output:
demo1.php
D:AppServwwwBasic6
basename : demo1.php
dirname: D:AppServwwwBasic6
extension: php
filename: demo1

2. Disk, directory and file count
1. View file size and disk space
filesize -- Get the file size
disk_free_space -- Return the available space in the directory
disk_total_space -- Return the total disk space of a directory Size

Copy code The code is as follows:

 
$path ='demo2.php'; 
$path = realpath($path); 
$drive = 'c:'; 
echo round(filesize($path)/1024,2).'kb'.'
 '; 
echo round(disk_free_space($drive)/1024/1024/1024,2).'GB'.'
'; 
echo round(disk_total_space($drive)/1024/ 1024/1024,2).'GB'.'
'; 
?> 

output
0.26kb
10.61GB
30.01 GB

2. Get various times of files
fileatime -- Get the last access time of the file
filectime -- Get the inode modification time of the file
filemtime -- Get the file modification time

Copy code The code is as follows:

 
$file = realpath ( '../Basic5/ demo3.php' ); 
$date_format = 'Y-m-d h:i:s'; 
echo 'lastest accessing time : '.date ( $date_format, fileatime ( $file ) ) . '
' ; 
echo 'lastest change time : '.date ( $date_format, filectime ( $file ) ) . '
'; 
echo 'lastest modify time : '.date ( $date_format, filemtime ( $ file ) ) . '
'; 
?> 

output
lastest accessing time : 2011-12-18 04:26:49
lastest change time : 2011-12-18 04:26:49
lastest modify time : 2011-12-18 04:29:15

三．文件处理
文件读写的两种方式：
1.php所有版本都支持的方法：
fopen -- 打开文件或者 URL
fclose -- 关闭一个已打开的文件指针
fwrite -- 写入文件（可安全用于二进制文件）
表 1. fopen() 中 mode 的可能值列表

mode	说明
'r'	只读方式打开，将文件指针指向文件头。
'r+'	读写方式打开，将文件指针指向文件头。
'w'	写入方式打开，将文件指针指向文件头并将文件大小截为零。如果文件不存在则尝试创建之。
'w+'	读写方式打开，将文件指针指向文件头并将文件大小截为零。如果文件不存在则尝试创建之。
'a'	写入方式打开，将文件指针指向文件末尾。如果文件不存在则尝试创建之。
'a+'	读写方式打开，将文件指针指向文件末尾。如果文件不存在则尝试创建之。
'x'	创建并以写入方式打开，将文件指针指向文件头。如果文件已存在，则 fopen() 调用失败并返回 FALSE，并生成一条 E_WARNING 级别的错误信息。如果文件不存在则尝试创建之。这和给底层的 open(2) 系统调用指定 O_EXCL\|O_CREAT 标记是等价的。此选项被 PHP 4.3.2 以及以后的版本所支持，仅能用于本地文件。
'x+'	创建并以读写方式打开，将文件指针指向文件头。如果文件已存在，则 fopen() 调用失败并返回 FALSE，并生成一条 E_WARNING 级别的错误信息。如果文件不存在则尝试创建之。这和给底层的 open(2) 系统调用指定 O_EXCL\|O_CREAT 标记是等价的。此选项被 PHP 4.3.2 以及以后的版本所支持，仅能用于本地文件。

复制代码代码如下:

 
$fp = fopen('file1.txt','w'); 
$outStr = "my name is anllin,\r\nmy age is 29."; 
fwrite($fp,$outStr,strlen($outStr)); 
fclose($fp); 
?> 

output
my name is anllin,
my age is 29.
2.php5新加入的方法
file_put_contents -- 将一个字符串写入文件

复制代码代码如下:

 
file_put_contents('file2.txt',"my name is anllin,\r\nmy age is 29."); 
?> 

output
my name is anllin,
my age is 29.
读出文件内容的方法：

函数	功能
Fgetc()	读出一个字符，并将指针移到下一个字符
Fgets()	读出一行字符，可以指定一行显示的长度。
Fgetss()	从文件指针中读取一行并过滤掉HTML标记
Fread()	读取定量的字符
Fpassthru()	输出文件到指定处的所有剩余数据
File()	将整个文件读入数组中，以行分组
Readfile()	读入一个文件并写入到输出缓冲
File_get_contents()	将整个文件读入一个字符串
Feof()	判断读完文件函数
File_exists()	查看文件是否存在

The content of the sample file file1.txt is as follows:
my name is anllin,
my age is 29.
fgetc -- Read characters from the file pointer
Demo.php

Copy code The code is as follows:

 
$fp = fopen('file1.txt','r'); 
echo fgetc($fp); 
echo fgetc($fp); 
fclose($fp); 
?> 

Output:
my
fgets -- Read a line from the file pointer

Copy the code The code is as follows:

 
$fp = fopen('file1.txt','r'); 
echo fgets($fp); 
echo fgets($fp); 
fclose($fp); 
? > 

output
my name is anllin, my age is 29.
fgetss -- Read a line from the file pointer and filter out HTML tags

Copy code The code is as follows:

 
$fp = fopen('file3.txt','w'); 
$outStr = "my name is anllin"; 
fwrite($fp,$outStr,strlen($outStr)); 
fclose($fp); 
$ ftp = fopen('file3.txt','r'); 
echo fgetss($ftp); 
fclose($ftp); 
?> 

Output
my name is anllin
fread -- read file (safe for binary files)

Copy code The code is as follows:

 
$filename = 'file1.txt'; 
$fp = fopen($filename,'r'); 
$contents = fread($fp,filesize ($filename)); 
echo $contents; 
fclose($fp); 
?> 

Output
my name is anllin, my age is 29 .
fpassthru -- Output all remaining data at the file pointer

Copy code The code is as follows:

 
$filename = 'file1.txt'; 
$fp = fopen($filename,'rb'); 
$leftSize = fpassthru($fp); 
echo $leftSize; 
fclose($fp); 
?> 

output
my name is anllin, my age is 29. 33
file -- Read the entire file into an array In

Copy code The code is as follows:

 
$lines = file('file1.txt' ); 
foreach ($lines as $line_num => $line) 
{ 
echo $line_num.' : '.$line.'
'; 
} 
 ?> 

output
0 : my name is anllin,
1 : my age is 29.
readfile -- Output a file

Copy code The code is as follows:

 
$size = readfile('file1.txt'); 
echo $size; 
?> 

output
my name is anllin, my age is 29.33
file_get_contents -- Read the entire file into a string (new in php5.0)

Copy code The code is as follows:

 
$contents = file_get_contents('file1.txt'); 
echo $contents; 
?> 

output
my name is anllin, my age is 29.
feof -- test whether the file pointer reaches the end of the file Location

Copy code The code is as follows:

 
$fp = fopen('file1.txt' ,'r'); 
while(!feof($fp)) 
{ 
echo fgetc($fp); 
} 
fclose($fp); 
?> ; 

output
my name is anllin, my age is 29.
file_exists -- Check whether the file or directory exists

Copy code The code is as follows:

 
 
< ;?php 
$filename = 'file1.txt'; 
if(file_exists($filename)) 
{ 
echo 'Perform file read and write operations'; 
} 
else 
{ 
echo 'The file you are looking for does not exist'; 
} 
?> 

output
Perform file read and write operations
filesize -- Get the file size

Copy code The code is as follows:

 
$file_size = filesize(' file1.txt'); 
echo $file_size; 
?> 

output
33
unlink -- 删除文件

复制代码代码如下:

 
$isDeleted = unlink('file3.txt'); 
echo $isDeleted; 
?> 

output
1
rewind -- 倒回文件指针的位置
ftell -- 返回文件指针读/写的位置
fseek -- 在文件指针中定位

复制代码代码如下:

 
$fp = fopen ( 'file1.txt', 'r' ); 
fgetc ( $fp ); 
fgetc ( $fp ); 
echo ftell ( $fp ) . '
'; 
rewind ( $fp ); 
echo ftell ( $fp ) . '
'; 
fgetc ( $fp ); 
fgetc ( $fp ); 
echo ftell ( $fp ) . '
'; 
fseek($fp,0);//same as rewind ($fp) 
echo ftell ( $fp ) . '
'; 
?> 

output
2
0
2
0
Flock的操作值

操作值	意义
LOCK_SH(以前为1)	读写锁定。这意味着文件可以共享，其他人可以读该文件
LOCK_EX(以前为2)	写操作锁定。这是互斥的，该文件不能被共享
LOCK_UN(以前为3)	释放已有的锁定
LOCK_NB(以前为4)	防止在请求加锁时发生阻塞

flock -- lightweight consultation file locking

Copy code The code is as follows:

 
$filename = 'file1.txt'; 
$fp = fopen($filename,'rb'); 
flock($fp,LOCK_EX);//locked 
$contents = fread($fp,filesize($ filename)); 
flock($fp,LOCK_UN);//unlocked 
echo $contents; 
fclose($fp); 
?> 

output
my name is anllin, my age is 29.
Directory handle operations
opendir -- open the directory handle
readdir -- read entries from the directory handle
closedir -- close the directory handle

Copy code The code is as follows:

 
$dir= opendir('../Basic6' ); 
while(!!$file = readdir($dir)) 
{ 
echo $file.'
'; 
} 
closedir($dir) ; 
?> 

output
.
..
.buildpath
.project
.settings
demo1.php
demo10.php
demo11.php
demo12.php
demo13.php
demo14.php
demo15.php
demo16.php
demo17.php
demo18. php
demo19.php
demo2.php
demo20.php
demo3.php
demo4.php
demo5.php
demo6.php
demo7.php
demo8.php
demo9.php
file1.txt
file2.txt
scandir -- List files and directories in the specified path

Copy the code The code is as follows:

 
$files = scandir('../Basic6'); 
foreach($files as $file ) 
{ 
echo $file.'
'; 
} 
?> 

output
.
..
.buildpath
.project
.settings
demo1.php
demo10.php
demo11.php
demo12.php
demo13.php
demo14.php
demo15.php
demo16.php
demo17.php
demo18.php
demo19.php
demo2.php
demo20.php
demo21.php
demo3.php
demo4.php
demo5.php
demo6.php
demo7.php
demo8.php
demo9.php
file1.txt
file2. txt
rename -- Rename a file or directory

Copy code The code is as follows:

 
rename('demo1.php','demo01.php'); 
if(file_exists('demo01.php')) 
{ 
echo 'file rename success'; 
} 
else 
{ 
echo 'file rename fail'; 
} 
?> 

output
file rename success
rmdir -- Delete Directory

Copy code The code is as follows:

 
rmdir('123'); 
 if(file_exists('123')) 
{ 
echo 'delete file fail'; 
} 
{ 
echo 'delete file success'; 
} 
?> ; 

output
delete file success