触发器自动选择下拉列表以显示其他隐藏字段

<select id="trigger" onchange="showFields()">
  <option value="option1">Option 1</option>
  <option value="option2">Option 2</option>
  <option value="option3">Option 3</option>
</select>

<input type="text" id="field1" style="display: none;">
<select id="field2" style="display: none;">
  <option value="value1">Value 1</option>
  <option value="value2">Value 2</option>
</select>

function showFields() {
  var trigger = document.getElementById("trigger");
  var field1 = document.getElementById("field1");
  var field2 = document.getElementById("field2");

  if (trigger.value === "option1") {
    field1.style.display = "block";
    field2.style.display = "none";
  } else if (trigger.value === "option2") {
    field1.style.display = "none";
    field2.style.display = "block";
  } else {
    field1.style.display = "none";
    field2.style.display = "none";
  }
}