JS实现select框实现模糊搜索

<select id="select">
  <option value="1">Apple</option>
  <option value="2">Banana</option>
  <option value="3">Cherry</option>
  <option value="4">Orange</option>
</select>

document.getElementById('select').addEventListener('input', function() {
  var input, filter, option, i;
  input = this.value;
  filter = input.toUpperCase();
  options = this.getElementsByTagName('option');
  
  for (i = 0; i < options.length; i++) {
    if (options[i].innerHTML.toUpperCase().indexOf(filter) > -1) {
      options[i].style.display = '';
    } else {
      options[i].style.display = 'none';
    }
  }
});