Propiedades calculadas y oyentes
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<ul>
<li>西游记; 价格：{
{xyjPrice}},数量：<input type="number" v-model="xyjNum"></li>
<li>西游记; 价格：{
{shzPrice}},数量：<input type="number" v-model="shzNum"></li>
<li>总价：{
{totalPrice}}</li>
</ul>
</div>
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
<script>
new Vue({
el:"#app",
data:{
xyjPrice:99.98,
shzPrice:98.00,
xyjNum: 1,
shzNum:1
},
computed:{
totalPrice(){
return this.xyjPrice*this.xyjNum + this.shzPrice*this.shzNum;
}
}
})
</script>
</body>
</html>
<body>
<div id="app">
<button v-on:click="count++">我被点击了{
{count}}次</button>
</div>
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
<script>
new Vue({
el:"#app",
data:{
count:1
}
})
</script>
</body> 
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<button v-on:click="count++">我被点击了{
{count}}次</button>
<counter></counter>
<counter></counter>
<counter></counter>
<counter></counter>
<counter></counter>
</div>
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
<script>
Vue.component("counter",{
template:`<button v-on:click="count++">我被点击了{
{count}}次</button>`,
data(){
return {
count:1
}
}
});
new Vue({
el:"#app",
data:{
count:1
}
})
</script>
</body>
</html> 
<button-counter></button-counter>