使用 JavaScript Proxy 实现简单的数据绑定

<body>
  hello,world
  <input type="text" id="model">
  <p id="word"></p>
</body>
<script>
  const model = document.getElementById("model")
  const word = document.getElementById("word")
  var obj= {};

  const newObj = new Proxy(obj, {
      get: function(target, key, receiver) {
        console.log(`getting ${key}!`);
        return Reflect.get(target, key, receiver);
      },
      set: function(target, key, value, receiver) {
        console.log('setting',target, key, value, receiver);
        if (key === "text") {
          model.value = value;
          word.innerHTML = value;
        }
        return Reflect.set(target, key, value, receiver);
      }
    });

  model.addEventListener("keyup",function(e){
    newObj.text = e.target.value
  })
</script>