title: Ajax file upload not working in laravel 5.6
body: <p>I am trying to upload csv file in laravel 5.6 using ajax request. But, the file could not be uploaded. It's showing, the file is required again and again.</p>
  
  <h1>form</h1>
  
  <pre><code>                    &lt;form class="form-horizontal file-upload" method="post" enctype="multipart/form-data"&gt;
                          {{ csrf_field() }}
                          &lt;input required="" type="file" name="import_file" id="import_file" /&gt;
                          &lt;br&gt;
                          &lt;br&gt;
                          &lt;button class="btn btn-success btn-sm" id="upload_csv" disabled="true" type="submit"&gt;Import CSV or Excel File&lt;/button&gt;
                      &lt;/form&gt;
  </code></pre>
  
  <h1>AJAX</h1>
  
  <pre><code>$(document).ready(function(){
          $('form').submit(function(event){
  
              event.preventDefault();
              var formData = new FormData($('this')[0]);
              $.ajax({
                  headers: { 'X-CSRF-TOKEN': $('meta[name="_token"]').attr('content') },
                  url: "{{url('admin/voter/sub/storecsv')}}",
                  data: formData,
                  type: 'post',
                  async: false,
                  processData: false,
                  contentType: false,
                  success:function(response){
                      // console.log(response);
                      alert('uploaded');
                  }
              });
  
          });
      });
  </code></pre>
  
  <h1>Controller</h1>
  
  <pre><code>$this-&gt;validate($request,[
      'import_file' =&gt; 'required',
  ]);
  </code></pre>
  
  <p>It shows that this import file is required. I have gone through many of other similar posts on stackoverflow and many other member seems to achieved success with the same code. But, I couldn't find what I have missed. Any help, would be appreciated.</p>