如何将表单操作与变量绑定？

// HTML
<input type="text" id="myInput">

// JavaScript
const myInput = document.getElementById('myInput');
let myVariable;

myInput.addEventListener('input', function() {
  myVariable = myInput.value;
});

<!-- HTML -->
<input type="text" v-model="myVariable">

<!-- JavaScript -->
new Vue({
  data: {
    myVariable: ''
  }
});

// HTML
<form action="/submit" method="post">
  <input type="text" name="myVariable">
  <button type="submit">Submit</button>
</form>

// JavaScript (Express)
const express = require('express');
const app = express();

app.use(express.urlencoded({ extended: false }));

app.post('/submit', (req, res) => {
  const myVariable = req.body.myVariable;
  // 处理表单数据
});