Selectlist onchange应在Razor页面中预填充文本字段值

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

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

<script>
  function updateTextField() {
    var selectValue = document.getElementById("mySelect").value;
    document.getElementById("myTextField").value = selectValue;
  }
</script>