PHP导出csv，防止内存泄漏 demo.php

<?php
/**
 * Created by PhpStorm.
 * User: kaiwu
 * Date: 2018/6/29
 * Time: 14:27
 */
//PHP大量数据导出方案（csv文件循环导出）
header('Content-disposition: attachment; filename=' . iconv('UTF-8', 'GBK', '结项导出信息') . date('Y_m_d_H_i_s') . '.csv');
$head = array(
    '城市',
    '姓名'
);
$head = u2g($head);
echo implode(',', $head)."\n";
$i = 0;
$count = 1000000;
do{
    $row = array();
    $row[0] = $i;
    $row[1] = $i+1;
    $lastArray = array();
    $lastArray[] = $row;
    foreach ($lastArray as $key => $val){
        echo implode(',', $val)."\n";
    }
    ob_flush();
    flush();
    $i=$i+2;
}while($i<=$count);


function u2g($in){
    if(is_array($in)) {
        foreach($in as $k=>$v) {
            $in[$k] = iconv('UTF-8','GBK//ignore',$v);
        }
    } else {
        $in = iconv('UTF-8','GBK//ignore',$in);
    }
    return $in;
}