1 <!doctype html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <meta name="viewport" 6 content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0"> 7 <meta http-equiv="X-UA-Compatible" content="ie=edge"> 8 <title>06计算属性computed使用</title> 9 <script src="https://cdn.bootcdn.net/ajax/libs/vue/3.2.40/vue.global.prod.js"></script> 10 </head> 11 <body> 12 <div id = "app"> 13 <!--计算属性--> 14 <button @click="desc()">减少</button>{{num}}<button @click="add()">增加</button> 15 <!--响应式数据--> 16 <div style="background-color: red;color: white">响应式数据: {{compute}}</div> 17 <div style="background-color: red;color: white" v-if="error">提示: {{error}}</div> 18 </div> 19 20 <script> 21 let app = Vue.createApp({ 22 data() { 23 return { 24 num: 1, 25 }; 26 }, 27 // 计算属性的特点是可以使用响应式数据(计算属性的调用方式跟data中属性的调用的方式是一样的) 28 computed: { 29 compute() { 30 return this.num; 31 }, 32 error() { 33 return this.num === 0 ? '不能小于0' : this.num === 10 ? '不能超过10' : '' 34 }, 35 }, 36 methods:{ 37 add(){ 38 // this表示当前的组件(当前是根组件,即下面的vm) 39 if (this.num < 10) this.num++; 40 }, 41 desc() { 42 if (this.num > 0) this.num--; 43 }, 44 }, 45 }); 46 47 let vm = app.mount('#app'); 48 </script> 49 </body> 50 </html>
标签:10,06,computed,app,num,return,属性 From: https://www.cnblogs.com/LiuChang-blog/p/16794194.html