<body> <input type="text" id="input" value=''> <h1 id="text"></h1> <button id="btn">點擊</button> </body>
/* 簡單模仿實現vue v-model */ var obj = { "value":9999 }; var i = 1; const input = document.getElementById('input'); const text = document.getElementById('text'); input.value = obj.value; text.innerHTML = obj.value; input.addEventListener('input',ev => { obj.value = input.value; i = 1; }) Object.defineProperty(obj,'value',{ get:() => { return }, set:(newVal) => { input.value = newVal; text.innerHTML = newVal; } }) //賦值,驗證值是否更改 const btn = document.getElementById('btn'); btn.addEventListener('click',() => { obj.value = '' obj.value = i++; })