举一个计算器的小例子：
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<body>
<!--父组件模板-->
<div id="app">
<child-cpn @increment="changeTotal" @decrement="changeTotal"></child-cpn>
<h2>点击次数：{{total}}</h2>
</div>
<template id="childCpn">
<div>
<button @click="increment">+1</button>
<button @click="decrement">-1</button>
</div>
</template>
<script src="../js/vue.js"></script>
<script>
let app=new Vue({
el:'#app',
data:{
total:0
},
methods:{
changeTotal(counter){
this.total=counter;
}
},
components:{
'child-cpn':{
template:'#childCpn',
data(){
return {
counter:0
}
},
methods:{
increment(){
this.counter++;
this.$emit('increment',this.counter)
},
decrement(){
this.counter--;
this.$emit('decrement',this.counter)
}
}
}
}
})
</script>
</body>
</html>
运行结果：
