您可以通过添加以下两行代码来做到这一点:

You can do it like this by adding 2 small lines of code:

var fileStatus = $('.fileStatus:last option:selected').val(); // <-- This line 
$(wrapper).append('<select name="pp_fileStatus[]" class="fileStatus"><option disabled="" selected="">Select</option><option value="1"> One</option><option value="2">Two</option><option value="3"> Three</option></select>');
$('.fileStatus:last').val(fileStatus); // <-- This line 

var fileStatus = $('.fileStatus:last option:selected').val();这将选择存在的最后一个dropdown的值.

$('.fileStatus:last').val(fileStatus);这将使用previous值设置最后一个dropdown(又名新创建的).

var fileStatus = $('.fileStatus:last option:selected').val(); this will select the value of the last dropdown that exist.

$('.fileStatus:last').val(fileStatus); this will set the last dropdown (aka the newly created) with the previous value.

演示

$(document).ready(function() {
  $('.fileStatus:first').change(function() {
    var fileStatus = $('.fileStatus option:selected').val();
    $('.fileStatus:last').val(fileStatus);
  })

  var wrapper = $(".appentInside .row"); //Fields wrapper
  var add_button = $(".click_me"); //Add button ID
  $(add_button).click(function(e) { //on add input button click
    e.preventDefault();
    var fileStatus = $('.fileStatus:last option:selected').val();
    $(wrapper).append('<select name="pp_fileStatus[]" class="fileStatus"><option disabled="" selected="">Select</option><option value="1"> One</option><option value="2">Two</option><option value="3"> Three</option></select>');
    $('.fileStatus:last').val(fileStatus);
  });

});

<select name="pp_fileStatus[]" class="fileStatus">
  <option disabled="" selected="">Select</option>
  <option value="1"> One</option>
  <option value="2"> Two</option>
  <option value="3"> Three</option>
</select>

<a href="javascript:void(0);" class="click_me">click me to display seocnd dropdown</a>
<div class="appentInside">
  <div class="row"></div>
</div>


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