将下拉列表中的选定项目放置到文本框中

<select id="mySelect">
  <option value="option1">选项1</option>
  <option value="option2">选项2</option>
  <option value="option3">选项3</option>
</select>

<input type="text" id="myText">

const select = document.getElementById("mySelect");
const text = document.getElementById("myText");

select.addEventListener("change", function() {
  text.value = select.value;
});