如何使一个值在选择后显示为另一个id

<select id="selectList" name="selectList">
  <option value="1">选项1</option>
  <option value="2">选项2</option>
  <option value="3">选项3</option>
</select>

document.getElementById("selectList").addEventListener("change", function() {
  var selectedValue = this.value;
  // 根据选中的值进行相应的操作
});

var displayId;
if (selectedValue === "1") {
  displayId = "id1";
} else if (selectedValue === "2") {
  displayId = "id2";
} else if (selectedValue === "3") {
  displayId = "id3";
}

var displayIdMap = {
  "1": "id1",
  "2": "id2",
  "3": "id3"
};
var displayId = displayIdMap[selectedValue];

document.getElementById(displayId).style.display = "block"; // 显示元素
document.getElementById(displayId).style.display = "none"; // 隐藏元素