<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
<!-- <script src="https://unpkg.com/vue@next"></script> -->
<script src="js/vue2.6.14/vue.js"></script>
<title></title>
</head>
<body>
<div id="app">
米:<input type="text" v-model:value="mi" ><br />
公里:<input type="text" v-model:value="m" >
</div>
<script>
var vm = new Vue({
el: "#app",
data: {
mi:0,
m:0
},
watch:{
mi(val){
this.mi=val;
this.m=this.mi/1000;
},
m(val){
this.m=val;
this.mi=this.m*1000;
}
}
});
</script>
</body>
</html>
用浏览器打开,然后输入数据即可