PHP AJAX-多个文件上传

Question

I want to upload multiple images with a Input file button via AJAX. For example if I upload two pictures I only get one picture instead of the two selected.

$('#uploadPic').submit(function(e) {
  e.preventDefault();
  var formData = new FormData($(this)[0]);

  $.ajax({
    type: 'post',
    url: 'example.com/post',
    data: formData,
    cache: false,
    contentType: false,
    processData: false,
    success: function(answ) {
      console.log(answ);
    }
  })
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

<form id="uploadPic" style="display: block;">
  <input required type="file" id="upload_button" name="images[]" multiple>
  <button type="submit">ok</button>
</form>

</div>