使用AJAX / jQuery / formData通过单个输入上传多个文件

I am trying to make an upload form with AJAX/jQuery. The problem is i can't upload multiple files from a single input. With this code I can upload 1 file:

HTML:

<form name="myform" id="myform" enctype="multipart/form-data">
    <input name="file[]" type="file" multiple />
    <input type="button" value="Upload" />
</form>

jQuery:

$(document).ready(function(){
  $(':button').click(function(){
  var formData = new FormData();
  formData.append('file', $('input[type=file]')[0].files[0]); 
    $.ajax({
      url: 'upload.php',
      type: 'POST',
      dataType:"json",
      async: true,
      success: function(data) {
        console.log(data.Result);
      },
    data: formData,
    cache: false,
    contentType: false,
    processData: false
    });
  });
});

I changed the formData part to this:

var formData = new FormData($('input[name^="file"]'));
$.each($('input[name^="file"]')[0].files, function(i, file){
 formData.append(i, file);
});

the PHP part:

foreach($_FILES as $index => $file)
    {
        // for easy access
        $fileName     = $file['name'];
        // for easy access
        $fileTempName = $file['tmp_name'];
        // check if there is an error for particular entry in array
        if(!empty($file['error'][$index]))
        {
            // some error occurred with the file in index $index
            // yield an error here
            return false;
        }

        // check whether file has temporary path and whether it indeed is an uploaded file
        if(!empty($fileTempName) && is_uploaded_file($fileTempName))
        {
            // move the file from the temporary directory to somewhere of your choosing
            move_uploaded_file($fileTempName, ROOT_DIR . '/uploads/xPhoto/' . $fileName);
            // mark-up to be passed to jQuery's success function.
            echo '<p>Click <strong><a href="uploads/' . $fileName . '" target="_blank">' . $fileName . '</a></strong> to download it.</p>';
        }
    }

So my question is, how can I upload multiple files with a single input?

you may need to include an index on file:

formData.append(i, file[i]);

This works for me. Let's you upload multiple files from single input. All accessible from the $_FILES global in php.

var formData = new FormData();
var files = $('#files_input').prop('files');

$.each(files, function(i, file) {
    formData.append("file_"  + i, file);
});