vue实现一个简易计算器

<div id="app">
    <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">
    <input @click="calc" type="button" value="=">
    <input type="text" v-model="result">


</div>

<script src="lib/vue.min.js"></script>
<script>
    var vm = new Vue({
        el: '#app',
        data: {
            n1: 0,
            n2: 0,
            result: 0,
            opt: "+"
        },
        methods: {
            calc() {
                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;
                }

                //正式开发中不建议这么用
                // var codeStr = 'parseInt(this.n1)' + this.opt + 'parseInt(this.n2)'
                // this.result = eval(codeStr);
            }
        }
    })
</script>