<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>ref方法</title>
<script src="https://unpkg.com/vue@next"></script>
</head>
<body>
<div id="app">
<post-item :post-content="content"></post-item>
</div>
<script>
const { ref, watchEffect } = Vue;
const state = ref(0)
watchEffect(() => {
document.body.innerHTML = `商品库存为:${state.value}台`
});
</script>
</body>
</html>