普通用法

<div id="div1">
	<input type="text" v-model="name">
	<p>
		{{name}}
	</p>
</div>
let vm=new Vue({
	el: '#div1',
	data: {
		name: 'blue'
	}
});

加法

<div id="div1">
	<input type="text" v-model="n1">+
	<input type="text" v-model="n2">=
	{{parseInt(n1)+parseInt(n2)}}
</div>

let vm=new Vue({
	el: '#div1',
	data: {
		n1: 0, n2: 0
	}
});

加法的另一种写法(推荐)

<div id="div1">
	<input type="text" v-model="n1">+
	<input type="text" v-model="n2">=
	{{sum()}}
</div>

let vm=new Vue({
	el: '#div1',
	data: {
		n1: 0, n2: 0
	},
	methods: {
		sum(){
			return parseInt(this.n1)+parseInt(this.n2);
		}
	}
});