JavaScript -选中选项时隐藏下拉菜单中的选项

// HTML代码
<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>

// JavaScript代码
var selectElement = document.getElementById("mySelect");
selectElement.addEventListener("change", function() {
  var selectedOption = selectElement.value;
  var options = selectElement.options;
  
  for (var i = 0; i < options.length; i++) {
    if (options[i].value === selectedOption) {
      options[i].style.display = "none";
    } else {
      options[i].style.display = "block";
    }
  }
});