how to use input type file and show selected file on screen
updateList = function() {
  var input = document.getElementById('file');
  var output = document.getElementById('fileList');
  output.innerHTML = '<ul>';
  for (var i = 0; i < input.files.length; ++i) {
    output.innerHTML += '<li>' + input.files.item(i).name + '</li>';
  }
  output.innerHTML += '</ul>';
}
