<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>天气案例_监视属性</title>
<!-- 引入Vue -->
<script type="text/javascript" src="../js/vue.js"></script>
</head>
<body>
<div id="root">
<h2>今天天气很{{info}}</h2>
<button @click="changeWeather">切换天气</button>
<hr>
<h3>a的值是：{{numbers.a}}</h3>
<button @click="numbers.a++">点我让a+1</button>
</div>
</body>
<script type="text/javascript">
Vue.config.productionTip = false
const vm = new Vue({
el: '#root',
data: {
isHot: true,
numbers:{
a:1,
b:1
}
},
computed: {
info() {
return this.isHot ? '炎热' : '凉爽'
}
},
methods: {
changeWeather() {
this.isHot = !this.isHot
}
},
watch:{
//正常写法
/* isHot:{
handler(newValue,oldValue){
console.log('isHot被修改了',newValue,oldValue)
}
}, */
isHot(newValue,oldValue){
console.log('asdasdasd')
}
}
})
vm.$watch('isHot',function(newValue,oldValue){
console.log('asdasdasd')
})
</script>
</html>
