为使Vue.js组件添加数据，使组件可以动态显示各种数据，注意是 数据函数而不是数据属性
<!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">
<script src="https://unpkg.com/vue/dist/vue.js"></script>
<title>Document</title>
</head>
<body>
<div id = "myApp">
<div>今天天气是<today-weather/></div>
</div>
<script>
Vue.component('today-weather',{
template:'<strong>{{todayweather}}</strong>',
data:function(){
return {
todayweather:'雨夹雪'
}
}
})
var myApp = new Vue({
el:"#myApp",
data:{
},
});
</script>
</body>
</html>