Ajax File Upload

ajaxUpload.js

       $('input#headshot').on('change',  (event) ->
          jQuery.active++ 
          files = event.target.files 
          formData = new FormData() 
 
          for file in files 
            formData.append('images[]', file, file.name) 
 
          xhr = new XMLHttpRequest() 
          xhr.open('POST', $(this).closest('form').attr('action'), true) 
          xhr.setRequestHeader('X-CSRF-Token', $('input[name="authenticity_token"]').attr('value')) 
          xhr.onreadystatechange = -> 
            if (xhr.readyState == 4 && xhr.status == 200) 
              eval(xhr.responseText) 
              jQuery.active-- 
          xhr.send(formData)
        )