php download remote pictures, compressed packages, PDFs and other files to the local area according to the URL

//Remote path, name, file suffixfunction downImgRar($url,$rename,$ext){
  switch ($ext) {
    case 'jpg':    //Download pictures      $file_path = 'uploads/images/';      
      break;
    case 'png':    //Download pictures      $file_path = 'uploads/images/';      
      break;
    case 'pdf':    //Download PDF      $file_path = 'uploads/pdf/';  
      break;
    case 'rar':    //Download the compressed package      $file_path = 'uploads/rar/';      
      break;
    case 'zip':    //Download the compressed package      $file_path = 'uploads/rar/';      
      break;
    default:
      $file_path = 'uploads/files/';      
    break;
  }
  $ch = curl_init($url);
  curl_setopt($ch, CURLOPT_HEADER, 0);
  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
  curl_setopt($ch, CURLOPT_BINARYTRANSFER,1);
  $rawdata=curl_exec ($ch);
  curl_close ($ch);
  // Use Chinese file name to transcode  $fp = fopen($file_path.iconv('UTF-8', 'GBK', $rename).".".$ext,'w');
  fwrite($fp, $rawdata);
  fclose($fp);
  // Return path  return $_SERVER['DOCUMENT_ROOT'].$file_path.$rename.".".$ext;
}

// Download the compressed packagefunction downRar($file_path)
{
  $file_name = '/uploads/rar/2009323162920-Vision C Yinqiao Film Manual.rar';
  $file_name = iconv("utf-8","gbk//IGNORE",$file_name); // Pay special attention! Pay special attention! Pay special attention here. Transcoding must be turned on under Windows, otherwise the direct file will not be stored  $file_path = $_SERVER['DOCUMENT_ROOT'] . $file_name;// For example, here under Windows, mine is "D:/web/public/uploads/rar/2009323162920-WeChat Yinqiao Film Manual.rar"  //Judge if the file exists, jump to the download path  if (!file_exists($file_path)) {
    die("The file does not exist!");
  }
  $fp = fopen($file_path, "r+") or die('Open file error');  //The file must be opened first when downloading it.  Write to memory  $file_size = filesize($file_path);
  //Returned file stream  Header("Content-type:application/octet-stream");
  //Return in byte format  Header("Accept-Ranges:bytes");
  //Return file size  Header("Accept-Length:" . $file_size);
  //The client dialog box pops up, the corresponding file name  Header("Content-Disposition:attachment;filename=" . substr($file_name, strrpos($file_name, '/') + 1));
  //Prevent the server from increasing pressure instantly and read in segments  $buffer = 1024;
  while (!feof($fp)) {
    $file_data = fread($fp, $buffer);
    echo $file_data;
  }
  fclose($fp);
  die("Download successfully!");
}