日期选择器未在javascript中显示年份和月份下拉列表

<select id="yearSelect"></select>
<select id="monthSelect"></select>

// 生成年份选项
var yearSelect = document.getElementById("yearSelect");
var currentYear = new Date().getFullYear();
for (var i = currentYear; i >= currentYear - 10; i--) {
  var option = document.createElement("option");
  option.value = i;
  option.text = i;
  yearSelect.appendChild(option);
}

// 生成月份选项
var monthSelect = document.getElementById("monthSelect");
for (var i = 1; i <= 12; i++) {
  var option = document.createElement("option");
  option.value = i;
  option.text = i;
  monthSelect.appendChild(option);
}