bcremer / line-reader
以内存高效(常数)的方式逐行读取大文件。
1.3.0
2023-01-27 12:08 UTC
Requires
- php: ^7.4 || ^8.0
Requires (Dev)
- friendsofphp/php-cs-fixer: 3.13.2
- infection/infection: ^0.26
- phpstan/phpstan: 1.9.14
- phpstan/phpstan-phpunit: 1.3.3
- phpunit/phpunit: ^9.4
This package is auto-updated.
Last update: 2024-08-29 04:25:25 UTC
README
LineReader 是一个库,用于以内存高效(常数)的方式逐行读取大文件。
安装
通过 Composer
$ composer require bcremer/line-reader
用法
假设我们有一个文本文件(some/file.txt
),其中包含类似以下内容的行
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Line 10
让我们假设命名空间已导入,以保持示例紧凑
use Bcremer\LineReader\LineReader;
正向读取
foreach (LineReader::readLines('some/file.txt') as $line) { echo $line . "\n" }
输出将是
Line 1
Line 2
Line 3
Line 4
Line 5
...
要设置偏移量或限制,请使用 \LimitIterator
$lineGenerator = LineReader::readLines('some/file.txt'); $lineGenerator = new \LimitIterator($lineGenerator, 2, 5); foreach ($lineGenerator as $line) { echo $line . "\n" }
将输出第 3 行到第 7 行
Line 3
Line 4
Line 5
Line 6
Line 7
反向读取
foreach (LineReader::readLinesBackwards('some/file.txt') as $line) { echo $line; }
Line 10
Line 9
Line 8
Line 7
Line 6
...
示例:以正向顺序读取最后 5 行
$lineGenerator = LineReader::readLinesBackwards('some/file.txt'); $lineGenerator = new \LimitIterator($lineGenerator, 0, 5); $lines = array_reverse(iterator_to_array($lineGenerator)); foreach ($line as $line) { echo $line; }
Line 6
Line 7
Line 8
Line 9
Line 10
测试
$ composer test
$ TEST_MAX_LINES=200000 composer test
许可证
MIT 许可证(MIT)。有关更多信息,请参阅许可证文件。