从csv文件中读取一列 awk 随机抽取 yield, generator, csv

* NameList.php

<?php
/**
 * Created by PhpStorm.
 * User: Mch
 * Date: 9/24/18
 * Time: 4:11 PM
 */
class NameList {
    private $handle = null;

    public function __construct($file) {
        $this->handle = fopen($file, 'rb');
        if ($this->handle === false) {
            throw new Exception('open file '.$file.' error');
        }
    }

    public function getYieldRows($length=256, $delimiter=' ') {
        while (feof($this->handle) === false) {
            yield fgetcsv($this->handle, $length, $delimiter);
        }
    }

    public function getListRows($length=256, $delimiter='', $col=0) {
        $list = new SplDoublyLinkedList();
        if ($col === 0) {
            $this->forEachLine(function($line) use ($list) {
                $list->push($line);
            }, $length);
        } else {
            $this->forEachLine(function($line) use ($list, $delimiter, $col) {
                $fields = explode($delimiter, $line);
                $list->push( $fields[$col-1] );
            }, $length);
        }

        return $list;
    }

    private function forEachLine(callable $handler, $length=256) {
        while (feof($this->handle) === false) {
            $line = fgets($this->handle, $length);
            call_user_func($handler, $line);
        }
    }

    public function __destruct() {
        fclose($this->handle);
    }

    public static function getRandom(SplDoublyLinkedList $list, int $n) : Array {
        $pick = [];
        while ($n-->0) {
            $i = rand(0, $list->count() - 1);
            array_push($pick, $list->offsetGet($i));
            $list->offsetUnset($i);
        }
        return $pick;
    }
}


<?php
/**
 * Created by