(PHP 4 >= 4.3.2, PHP 5, PHP 7)
streamWrapper::dir_readdir — Read entry from directory handle
This method is called in response to readdir().
此函数没有参数。
Should return string representing the next filename, or
FALSE if there is no next file.
Note:
The return value will be casted to string.
调用此方法失败将给出
E_WARNING（未实现）。
Example #1 Listing files from tar archives
<?php
class streamWrapper {
protected $fp;
public function dir_opendir($path, $options) {
$url = parse_url($path);
$path = $url["host"] . $url["path"];
if (!is_readable($path)) {
trigger_error("$path isn't readable for me", E_USER_NOTICE);
return false;
}
if (!is_file($path)) {
trigger_error("$path isn't a file", E_USER_NOTICE);
return false;
}
$this->fp = fopen($path, "rb");
return true;
}
public function dir_readdir() {
// Extract the header for this entry
$header = fread($this->fp, 512);
$data = unpack("a100filename/a8mode/a8uid/a8gid/a12size/a12mtime/a8checksum/a1filetype/a100link/a100linkedfile", $header);
// Trim the filename and filesize
$filename = trim($data["filename"]);
// No filename? We are the end of the archive
if (!$filename) {
return false;
}
$octal_bytes = trim($data["size"]);
// Filesize is defined in octects
$bytes = octdec($octal_bytes);
// tar rounds up filesizes up to multiple of 512 bytes (zero filled)
$rest = $bytes % 512;
if ($rest > 0) {
$bytes += 512 - $rest;
}
// Seek over the file
fseek($this->fp, $bytes, SEEK_CUR);
return $filename;
}
public function dir_closedir() {
return fclose($this->fp);
}
public function dir_rewinddir() {
return fseek($this->fp, 0, SEEK_SET);
}
}
stream_wrapper_register("tar", "streamWrapper");
$handle = opendir("tar://example.tar");
while (false !== ($file = readdir($handle))) {
var_dump($file);
}
echo "Rewinding..\n";
rewind($handle);
var_dump(readdir($handle));
closedir($handle);
?>
以上例程的输出类似于：
string(13) "construct.xml" string(16) "dir-closedir.xml" string(15) "dir-opendir.xml" string(15) "dir-readdir.xml" string(17) "dir-rewinddir.xml" string(9) "mkdir.xml" string(10) "rename.xml" string(9) "rmdir.xml" string(15) "stream-cast.xml" string(16) "stream-close.xml" string(14) "stream-eof.xml" string(16) "stream-flush.xml" string(15) "stream-lock.xml" string(15) "stream-open.xml" string(15) "stream-read.xml" string(15) "stream-seek.xml" string(21) "stream-set-option.xml" string(15) "stream-stat.xml" string(15) "stream-tell.xml" string(16) "stream-write.xml" string(10) "unlink.xml" string(12) "url-stat.xml" Rewinding.. string(13) "construct.xml"