Vue监听属性
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<html><head><meta charset="utf-8"><title>監(jiān)聽屬性</title><script src="js/vue.js"></script></head><body><div id="app"><p style="font-size:25px;">計數(shù)器:{{counter}}</p><button @click="counter++" style="font-size:25px;">點我</button></div><div id="computed_propos">千米:<input type="text" v-model="kilometers" />米:<input type="text" v-model="meters" /><p id="info"></p></div><script>var vm = new Vue({el: '#app',data: {counter: 1}});vm.$watch('counter', function(nval, oval) {alert('計數(shù)器值的變化:' + oval + '變?yōu)?#39; + nval + '!');});var v = new Vue({el: '#computed_propos',data: {kilometers: 0,meters: 0},methods: {},computed: {},watch: {kilometers: function(val) {this.kilometers = val;this.meters = this.kilometers * 1000},meters: function(val) {this.kilometers = val / 1000;this.meters = val;}}})// $watch 是一個實例方法v.$watch('kilometers', function(newValue, oldValue) {// 這個回調(diào)將在 vm.kilometers 改變后調(diào)用document.getElementById("info").innerHTML = "修改前值為:" + oldValue + ",修改后值為:" + newValue;})</script></body>
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總結(jié)