<!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>computed用法</title>
<script src="https://cdn.staticfile.org/vue/3.0.5/vue.global.js"></script>
</head>
<body>
<div id="app">
<input type="number" v-model="a">+
<input type="number" v-model="b">
<input type="text" v-model="c">
</div>
<script>
const app = {
data() {
return {
a: 0,
b: 0
}
},
//computed 存在缓存 1.首次加载时会调用 2.当计算属性所依赖的字段发生改变时会调用（更新）
computed: {
c: {
get() {
return parseInt(this.a) + parseInt(this.b);
},
set() {
// console.log("data.c" +
// this._data.c);
console.log("set");
}
},
//如果没有set方法可以简写为
// c() {
// return parseInt(this.a) + parseInt(this.b);
// }
}
};
const vm = Vue.createApp(app).mount("#app");
</script>
</body>
</html>