如何使用JavaScript生成动态选择框？

<select id="dynamicSelect"></select>

var selectBox = document.getElementById("dynamicSelect");
var options = ["选项1", "选项2", "选项3"];

for (var i = 0; i < options.length; i++) {
  var option = document.createElement("option");
  option.text = options[i];
  selectBox.add(option);
}

// 清空选择框
selectBox.innerHTML = "";

// 添加新的选项
var newOptions = ["新选项1", "新选项2", "新选项3"];
for (var i = 0; i < newOptions.length; i++) {
  var option = document.createElement("option");
  option.text = newOptions[i];
  selectBox.add(option);
}