作用:数据双向绑定
注意:绑定的是表单控件
实现了计算器功能 代码与效果如下
<!DOCTYPE html>
<html>
<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></title>
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
</head>
<body>
<div id='app'>
<!-- 计算器: -->
<input type="text" v-model:value="num1">
<select name="" id="" v-model="operator" >
<option value="+">+</option>
<option value="-">-</option>
<option value="*">*</option>
<option value="/">/</option>
</select>
<input type="text" v-model:value="num2">
<button @click="sum">=</button>
<input type="text" v-model="num3">
</div>
<script>
const vm = new Vue({
el: '#app',
data: {
num1:"",
num2:"",
num3:"",
operator:""
},
methods: {
sum(){
if(this.operator=='+'){
this.num3 = Number(this.num1) + Number(this.num2)
}
if(this.operator=='-'){
this.num3 = Number(this.num1) - Number(this.num2)
}
if(this.operator=='*'){
this.num3 = Number(this.num1) * Number(this.num2)
}
if(this.operator=='/'){
this.num3 = Number(this.num1) / Number(this.num2)
}
},
},
})
</script>
</body>
</html>