使用表单选择选项值访问数组中的json数组

<form>
  <select id="option">
    <option value="1">Option 1</option>
    <option value="2">Option 2</option>
    <option value="3">Option 3</option>
  </select>
  <button type="button" onclick="getSelectedOption()">Submit</button>
</form>

<script>
  function getSelectedOption() {
    var selectedOption = document.getElementById("option").value;
    // 发送选项值到服务器端
    fetch('/getMatchedItem', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({ option: selectedOption })
    })
    .then(response => response.json())
    .then(data => {
      // 处理服务器返回的匹配项数据
      console.log(data);
    })
    .catch(error => {
      console.error('Error:', error);
    });
  }
</script>

const express = require('express');
const app = express();
const bodyParser = require('body-parser');

// 解析请求体中的JSON数据
app.use(bodyParser.json());

app.post('/getMatchedItem', (req, res) => {
  const selectedOption = req.body.option;
  const jsonArray = [
    { id: 1, name: 'Item 1' },
    { id: 2, name: 'Item 2' },
    { id: 3, name: 'Item 3' }
  ];

  // 在JSON数组中查找匹配项
  const matchedItem = jsonArray.find(item => item.id === parseInt(selectedOption));

  // 返回匹配项给前端
  res.json(matchedItem);
});

app.listen(3000, () => {
  console.log('Server is running on port 3000');
});