根据我选择的值隐藏select选项

<select id="mySelect">
  <option value="1">选项1</option>
  <option value="2">选项2</option>
  <option value="3">选项3</option>
  <option value="4">选项4</option>
</select>

document.getElementById("mySelect").addEventListener("change", function() {
  var selectedValue = this.value;
  var options = document.getElementById("mySelect").options;

  for (var i = 0; i < options.length; i++) {
    var optionValue = options[i].value;

    if (optionValue === "2" || optionValue === "3") {
      options[i].style.display = "none";
    } else {
      options[i].style.display = "block";
    }
  }
});