Question

我正在使用以下脚本，如果某人从多个下拉列表中选择了相同的值，则会显示弹出错误。效果很好，但是在显示弹出窗口后，仍然会发生重复选择。它应该防止这种情况发生。

$(document).ready(function () {
    $('select').change(function () {
        if ($('select option[value="' + $(this).val() + '"]:selected').length > 1) {
            alert('You have already selected this option previously - please choose another.')
        }
    });
});

jsfiddle example here

Answer 1

您可以切换到默认选项：

$(this).val('-1').change();

希望这有帮助。

＆＃13;

$(document).ready(function () {
  $('select').change(function () {
    if ($('select option[value="' + $(this).val() + '"]:selected').length > 1) {
      $(this).val('-1').change();
      alert('You have already selected this option previously - please choose another.')
    }
  });
});

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<select>
  <option value='-1'>Choose an option</option>
  <option value='1'>option 1</option>
  <option value='2'>option 2</option>
  <option value='3'>option 3</option>
</select>

<select>
  <option value='-1'>Choose an option</option>
  <option value='4'>option 4</option>
  <option value='1'>option 1</option>
  <option value='5'>option 5</option>
</select>

＆＃13;

Answer 2

一个选项是赋值0以强制选择新值，类似这样的

jQuery(document).ready(function () {

    $('select').change(function () {

        if ($('select option[value="' + $(this).val() + '"]:selected').length > 1)
        {
            $(this).val(0);
            alert('You have already selected this company - please choose another.')
        }
    });
});

防止在多个下拉列表中重复选择

2 个答案: