根据选择的值更改为ComboBox的背景/文本颜色

<select id="myComboBox" onchange="changeColor()">
  <option value="red">Red</option>
  <option value="green">Green</option>
  <option value="blue">Blue</option>
</select>

function changeColor() {
  var comboBox = document.getElementById("myComboBox");
  var selectedValue = comboBox.value;
  
  if (selectedValue === "red") {
    comboBox.style.backgroundColor = "red";
    comboBox.style.color = "white";
  } else if (selectedValue === "green") {
    comboBox.style.backgroundColor = "green";
    comboBox.style.color = "white";
  } else if (selectedValue === "blue") {
    comboBox.style.backgroundColor = "blue";
    comboBox.style.color = "white";
  }
}

import React, { useState } from "react";

function ComboBox() {
  const [selectedValue, setSelectedValue] = useState("");

  const changeColor = (event) => {
    setSelectedValue(event.target.value);
  };

  return (
    <select onChange={changeColor}>
      <option value="red">Red</option>
      <option value="green">Green</option>
      <option value="blue">Blue</option>
    </select>
  );
}