PHP内存溢出优化代码详解

<?php

namespace api\service;

class exportservice
{

 public static $outputfile = '';

 /**
 * 导出文件
 * @param string $filename
 * @param $data
 * @param array $formfields
 * @return mixed
 */
 public static function exportdata($filename = '', $data, $formfields = [])
 {
 $filearr = [];
 $tmppath = \yii::$app->params['excelsavepath'];

 foreach (array_chunk($data, 10000) as $key => $value) {
  self::$outputfile = '';
  $subject  = !empty($filename) ? $filename : 'data_';
  $subject  .= date('ymdhis');
  if (empty($value) || empty($formfields)) {
  continue;
  }

  self::$outputfile = $tmppath . $subject . $key . '.csv';
  if (!file_exists(self::$outputfile)) {
  touch(self::$outputfile);
  }
  $index = array_keys($formfields);
  $header = array_values($formfields);
  self::output($header);

  foreach ($value as $k => $v) {
  $tmpdata = [];
  foreach ($index as $item) {
   $tmpdata[] = isset($v[$item]) ? $v[$item] : '';
  }
  self::output($tmpdata);
  }
  $filearr[] = self::$outputfile;
 }
 
 $zipfile = $tmppath . $filename . date('ymdhi') . '.zip';
 $zipres = self::zipfile($filearr, $zipfile);
 return $zipres;
 }

 /**
 * 向文件写入数据
 * @param array $data
 */
 public static function output($data = [])
 {
 if (is_array($data) && !empty($data)) {
  $data = implode(',', $data);
  file_put_contents(self::$outputfile, iconv("utf-8", "gb2312//ignore", $data) . php_eol, file_append);
 }
 }

 /**
 * 压缩文件
 * @param $sourcefile
 * @param $distfile
 * @return mixed
 */
 public static function zipfile($sourcefile, $distfile)
 {
 $zip = new \ziparchive();
 if ($zip->open($distfile, \ziparchive::create) !== true) {
  return $sourcefile;
 }

 $zip->open($distfile, \ziparchive::create);
 foreach ($sourcefile as $file) {
  $filecontent = file_get_contents($file);
  $file = iconv('utf-8', 'gbk', basename($file));
  $zip->addfromstring($file, $filecontent);
 }
 $zip->close();
 return $distfile;
 }
 
 /**
 * 下载文件
 * @param $filepath
 * @param $filename
 */
 public static function download($filepath, $filename)
 {
 if (!file_exists($filepath . $filename)) {
  header('http/1.1 404 not found');
 } else {
  //以只读和二进制模式打开文件
  $file = fopen($filepath . $filename, "rb");

  //告诉浏览器这是一个文件流格式的文件
  header("content-type: application/octet-stream");
  //请求范围的度量单位
  header("accept-ranges: bytes");
  //content-length是指定包含于请求或响应中数据的字节长度
  header("accept-length: " . filesize($filepath . $filename));
  //用来告诉浏览器，文件是可以当做附件被下载，下载后的文件名称为$file_name该变量的值
  header("content-disposition: attachment; filename=" . $filename);

  //读取文件内容并直接输出到浏览器
  echo fread($file, filesize($filepath . $filename));
  fclose($file);
  exit();
 }
 }
}

$filename = "库存导入模板";
$stockres = []; // 导出的数据
$formfields = [
 'store_id' => '门店id',
 'storename' => '门店名称',
 'sku' => 'sku编码',
 'name' => 'sku名称',
 'stock' => '库存',
 'reason' => '原因'
];
$fileres = exportservice::exportdata($filename, $stockres, $formfields);
$tmppath = \yii::$app->params['excelsavepath']; // 文件路径
$filename = str_replace($tmppath, '', $fileres);

// 下载文件
exportservice::download($tmppath, $filename);