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);