This article will give you a summary of some commonly used folder/file directory operation functions in PHP. These Just a brief introduction to some basic methods as a note.
1. Create directory (mkdir)
bool mkdir (string $pathname [,int $mode [,bool $recursive [,resource $context ]]] )
<?php
mkdir("/path/to/my/dir", 0777); //成功返回true,失败返回false;2. Determine whether the file exists (file_exist)
bool file_exists (string $filename )
<?php $filename = '/path/to/phpernote.txt'; echo file_exists($filename)?'文件存在':'文件不存在';
3. Check whether the specified file is a directory, which is generally used to determine whether the directory exists (is_dir)
bool is_dir (string $filename )
<?php
var_dump(is_dir('a_file.txt'));// 输出false
var_dump(is_dir('wwwroot/phpernote')); //相对当前目录检查wwwroot/phpernote目录是否存在，存在输出true，不存在输出false
var_dump(is_dir('..')); //输出trueNote: The result of this function will be cached. Please use clearstatcache() to clear the cache.
4. Determine whether the given file name is a normal file (is_file)
bool is_file ( string $filename )
<?php
var_dump(is_file('a_file.txt'));//true
var_dump(is_file('/usr/bin/'));//false5. Lock or release files (flock)
bool flock ( string $filename, string $lock [,mix $block] )
The lock parameter can be one of the following values:
To obtain a shared lock (reading program), set lock to LOCK_SH (set to 1 in versions prior to PHP 4.0.1).
To obtain an exclusive lock (writing program), set lock to LOCK_EX (set to 2 in versions prior to PHP 4.0.1).
To release a lock (whether shared or exclusive), set lock to LOCK_UN (set to 3 in versions prior to PHP 4.0.1).
If you do not want flock() to block on lock, add LOCK_NB to lock (set to 4 in versions prior to PHP 4.0.1).
block optional. If set to 1 or true, blocks other processes while locking.
Tip: You can use fclose() to release the lock operation, which will be automatically called when the code is executed. For example:
<?php
$file = fopen("test.txt","w+");
// 排它性的锁定
if (flock($file,LOCK_EX)){
if(is_writable($file))
fwrite($file,"www.phpernote.com 总结的文章");
// 解锁
flock($file,LOCK_UN);
}else{
echo "锁定文件失败!";
}
fclose($file);6. Determine whether the given file name is a symbolic link (is_link)
bool is_link ( string $filename )
<?php
var_dump(is_link("a.lnk")); //输出trueNote: The result of this function will be cached. Please use clearstatcache() to clear the cache.
7. Delete directory (rmdir) This function only deletes empty directories (rmdir)
bool rmdir ( string $dirname )
<?php
var_dump(rmdir("/usr/local/a")); //当a为空目录删除成功，a为非空目录删除失败8. Delete files (unlink)
bool unlink ( string $filename )
<?php
while(is_file($wwwphpernotecom) == TRUE){
chmod($wwwphpernotecom, 0666);//设置可读取，可写入权限
unlink($wwwphpernotecom);
}9. Obtain permissions for files or directories (fileperms)
mix fileperms ( filename )
<?php
//若成功，则返回文件的访问权限。若失败，则返回 false
echo fileperms("test.txt");//输出：33206Return permissions as octal value
<?php
echo substr(sprintf("%o",fileperms("test.txt")),-4);//输出：1777Tip: The result of this function will be cached. Please use clearstatcache() to clear the cache.
10. Get the type of the specified file or directory (filetype)
mix filetype ( filename )
If successful, return 7 possible values (fifo char dir block link file unknown). On failure, returns false. For example:
<?php
echo filetype("test.txt");//输出：fileTip: The result of this function will be cached. Please use clearstatcache() to clear the cache.
11. Read directory files (opendir readir closedir)
resource opendir ( string $path [,resource $context ] )
Opens a directory handle that can be used in subsequent closedir(), readdir() and rewinddir() calls.
string readdir ( resource $dir_handle )
Returns the filename of the next file in the directory. File names are returned in order in the file system.
void closedir ( resource $dir_handle )
Close the directory stream specified by dir_handle. The stream must have been previously opened by opendir().
void rewinddir ( resource $dir_handle )
Resets the directory stream specified by dir_handle to the beginning of the directory.
The following is a complete example of reading a directory file:
<?php
$dir = "/etc/php5/";
if (is_dir($dir)) {
if ($dh = opendir($dir)) {
while (($file = readdir($dh)) !== false) {
echo "文件名: $file : 文件类型: " . filetype($dir . $file) . "\n";
}
closedir($dh);
}
}12. Rename files or directories （rename）
bool rename ( oldname, newname, context )
<?php
//将当前目录下的子目录a下面的文件1.gif重命名为2.gif
rename('/a/1.gif', '/a/2.gif');Note: The same goes for directories. The system will return the operation result, TRUE if successful, and FALSE if failed.
If you want to move a file or directory, just set the renamed path to the new path, for example:
<?php
//将当前目录下的子目录a下面的文件1.gif，移动到当前目录下的子目录b,并且重命名为2.gif
rename('/a/1.gif', '/b/2.gif');
//注意：如果目录b不存在，就会移动失败13. Copy (copy) files (copy)
bool copy (source, destination)
<?php
//将当前目录下的子目录a下面的文件1.gif，复制到当前目录下的子目录b，并命名为2.gif
copy('/a/1.gif', '/b/1.gif');Note: This operation cannot be performed on the directory; if the target file (/b/1.gif above) already exists, the original file will be overwritten; if you want to move the file, please use the rename() function.
14. Get the free space of the directory (disk_free_space)
disk_free_space ( directory )
<?php
echo disk_free_space("C:");//输出：20969328855815. Determine whether the specified file is writable (is_writable or is_writeable)
bool is_writable ( file )
说明：如果文件存在并且可写则返回 true；file 参数可以是一个允许进行是否可写检查的目录名；本函数的结果会被缓存。请使用 clearstatcache() 来清除缓存。例如：
<?php $file = "test.txt"; //或者：$file = 'd:\wwwroot\phpernote\'; echo is_writable($file)?'可写':'不可写';
16、以读写（w+）模式建立一个具有唯一文件名的临时文件（tmpfile）
resource tmpfile()
<?php $temp = tmpfile(); fwrite($temp, "Testing, www.phpernote.com"); //倒回文件的开头 rewind($temp); //从文件中读取 1k echo fread($temp,1024); //删除文件 fclose($temp); //文件会在关闭后（用 fclose()）自动被删除，或当脚本结束后 //输出：Testing, www.phpernote.com
17、改变文件权限模式（chmod）
bool chmod ( file [,mode] )
mode 可选。规定新的权限。该参数由 4 个数字组成：
第一个数字永远是 0
第二个数字规定所有者的权限
第二个数字规定所有者所属的用户组的权限
第四个数字规定其他所有人的权限
可能的值（如需设置多个权限，请对下面的数字进行总计）：
1 - 执行权限
2 - 写权限
4 - 读权限
<?php
// 所有者可读写，其他人没有任何权限
chmod("test.txt",0600);
// 所有者可读写，其他人可读
chmod("test.txt",0644);
// 所有者有所有权限，其他所有人可读和执行
chmod("test.txt",0755);
// 所有者有所有权限，所有者所在的组可读
chmod("test.txt",0740);18、扩展函数，方法
php读取目录并列表显示目录中的文件的函数
PHP删除目录及目录下所有文件
更多文件，文件夹（目录）函数请参考：
PHP Filesystem 函数
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