filesize

作用：函数返回指定文件的大小

语法：

filesize(filename)

参数：

filename：必需。规定要检查的文件。

返回值：

返回文件大小的字节数，如果出错返回 FALSE 并生成一条 E_WARNING 级的错误。

filesize 示例

示例一

1. <?php
2. // 输出类似：somefile.txt: 1024 bytes
3. $filename = 'somefile.txt';
4. echo $filename . ': ' . filesize($filename) . ' bytes';
5. ?>

示例二

1. <?php
2. function human_filesize($bytes, $decimals = 2) {
3. $sz = 'BKMGTP';
4. $factor = floor((strlen($bytes) - 1) / 3);
5. return sprintf("%.{$decimals}f", $bytes / pow(1024, $factor)) . @$sz[$factor];
6. }
7. ?>

示例三

1. <?php
2. /**
3. * Converts bytes into human readable file size.
4. *
5. * @param string $bytes
6. * @return string human readable file size (2,87 Мб)
7. * @author Mogilev Arseny
8. */
9. function FileSizeConvert($bytes)
10. {
11. $bytes = floatval($bytes);
12. $arBytes = array(
13. 0 => array(
14. "UNIT" => "TB",
15. "VALUE" => pow(1024, 4)
16. ),
17. 1 => array(
18. "UNIT" => "GB",
19. "VALUE" => pow(1024, 3)
20. ),
21. 2 => array(
22. "UNIT" => "MB",
23. "VALUE" => pow(1024, 2)
24. ),
25. 3 => array(
26. "UNIT" => "KB",
27. "VALUE" => 1024
28. ),
29. 4 => array(
30. "UNIT" => "B",
31. "VALUE" => 1
32. ),
33. );
34. foreach($arBytes as $arItem)
35. {
36. if($bytes >= $arItem["VALUE"])
37. {
38. $result = $bytes / $arItem["VALUE"];
39. $result = str_replace(".", "," , strval(round($result, 2)))." ".$arItem["UNIT"];
40. break;
41. }
42. }
43. return $result;
44. }
45. ?>

示例四

1. <?php
2. /**
3. * Return file size (even for file > 2 Gb)
4. * For file size over PHP_INT_MAX (2 147 483 647), PHP filesize function loops from -PHP_INT_MAX to PHP_INT_MAX.
5. *
6. * @param string $path Path of the file
7. * @return mixed File size or false if error
8. */
9. function realFileSize($path)
10. {
11. if (!file_exists($path))
12. return false;
13. $size = filesize($path);
14. if (!($file = fopen($path, 'rb')))
15. return false;
16. if ($size >= 0)
17. {//Check if it really is a small file (< 2 GB)
18. if (fseek($file, 0, SEEK_END) === 0)
19. {//It really is a small file
20. fclose($file);
21. return $size;
22. }
23. }
24. //Quickly jump the first 2 GB with fseek. After that fseek is not working on 32 bit php (it uses int internally)
25. $size = PHP_INT_MAX - 1;
26. if (fseek($file, PHP_INT_MAX - 1) !== 0)
27. {
28. fclose($file);
29. return false;
30. }
31. $length = 1024 * 1024;
32. while (!feof($file))
33. {//Read the file until end
34. $read = fread($file, $length);
35. $size = bcadd($size, $length);
36. }
37. $size = bcsub($size, $length);
38. $size = bcadd($size, strlen($read));
39. fclose($file);
40. return $size;
41. }