js判断listbox是否选中

<select id="singleSelect">
  <option value="1">Option 1</option>
  <option value="2" selected>Option 2</option>
  <option value="3">Option 3</option>
</select>

<script>
  function isOptionSelected(selectId, value) {
    const selectElement = document.getElementById(selectId);
    return selectElement.value === value;
  }

  console.log(isOptionSelected('singleSelect', '2')); // 输出: true
  console.log(isOptionSelected('singleSelect', '1')); // 输出: false
</script>

<select id="multiSelect" multiple>
  <option value="1">Option 1</option>
  <option value="2" selected>Option 2</option>
  <option value="3" selected>Option 3</option>
</select>

<script>
  function isOptionSelected(selectId, value) {
    const selectElement = document.getElementById(selectId);
    return Array.from(selectElement.options).some(option => option.value === value && option.selected);
  }

  console.log(isOptionSelected('multiSelect', '2')); // 输出: true
  console.log(isOptionSelected('multiSelect', '1')); // 输出: false
</script>