选择指定值时，清除select2倍数

Question

我尝试在select2 multiple select中实现以下场景。

1. 用户选择一些选项
2. 用户在选择
中选择“无需要的程序”
3. 选择清除所有选定的值
4. Select有一个占位符，其中包含以下文本：'No Required Features'

这是我的HTML：

<select multiple="multiple" name="transfer_posting[pap_facility_feature_ids][]" id="transfer_posting_pap_facility_feature_ids"><option value="No Required Features">No Required Features</option>
  <option value="13">Pool</option>
  <option value="15">Sauna</option>
  <option value="16">Salon</option>
  <option value="17">Massage</option>
</select> 

和javascript：

$('#transfer_posting_pap_facility_feature_ids').select2({
  placeholder: 'Select Feature(s)',
  allowClear: true
});

$('#transfer_posting_pap_facility_feature_ids').on("select2:selecting", function(e) {
  var selectedFeature = e.params.args.data.text
    console.log(selectedFeature);
  if (selectedFeature === 'No Required Features') {
    $('#transfer_posting_pap_facility_feature_ids').val(null).trigger("change");

    $('#transfer_posting_pap_facility_feature_ids').select2({
      placeholder: 'No Required Features'
    });

  }
});

以下是js小提琴的链接：http://jsfiddle.net/mxqc76e8/3/

如何更新代码以使此方案有效？

Answer 1

请查看更新的小提琴代码。 Updated Fiddle
添加了一些条件，代码更改了一点 希望它能帮到你

$('#transfer_posting_pap_facility_feature_ids').select2({
  placeholder: 'Select Feature(s)',
  allowClear: true
});

$('#transfer_posting_pap_facility_feature_ids').on("select2:selecting", function(e) {
    if ($("#transfer_posting_pap_facility_feature_ids option[value='No Required Features']:selected").length > 0){
    alert('No Required Feture is selected');
    exit;
    }
  var selectedFeature = e.params.args.data.text
 if (selectedFeature =='No Required Features') {    
    $('#transfer_posting_pap_facility_feature_ids').select2({
      placeholder: 'No Required Features'
    });
    $('li.select2-selection__choice').remove();
  $('#transfer_posting_pap_facility_feature_ids').val('');
  }
});