v-model用于数据的双向绑定。bug不少，凑合看吧，主要是练习v-model。
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <title>Document</title> <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script> </head> <body> <div id="app"> <!-- v-model 双向绑定数据 --> <input type="text" v-model="n1"> <select v-model="opt"> <option value="+">+</option> <option value="-">-</option> <option value="*">*</option> <option value="/">/</option> </select> <input type="text" v-model="n2"> <!-- @ 用于事件绑定 --> <input type="button" value="=" @click="cal"> <input type="text" v-model="result"> </div> </body> <script> let vm = new Vue({ el: '#app', data: { n1: 0, n2: 0, result: 0, opt: '+' }, methods: { cal(){ switch(this.opt){ case '+': this.result = parseInt(this.n1) + parseInt(this.n2) break case '-': this.result = parseInt(this.n1) - parseInt(this.n2) break case '*': this.result = parseInt(this.n1) * parseInt(this.n2) break case '/': this.result = parseInt(this.n1) / parseInt(this.n2) break } } } }) </script> </html>