vue.js引用背景图background无效的3种解决方案

<template>
  <div class="demo">
    <!-- 成功引入的三种方法： -->
    <!-- 图1 -->
    <div class="img1"></div>
    <!-- 图2 -->
    <div class="img2" :style="{backgroundImage: 'url(' + bg2 + ')' }"></div>
    <!-- 图3 -->
    <img src="~@/../static/images/logo3.png" width="100">
  </div>
</template>

<script>
import Bg2 from '@/../static/images/logo2.png'
export default {
	name: 'App',
	data () {
	    return {
			bg2: Bg2,
	    }
	}
}
</script>

<style>
	.demo{width: 100px;margin: 50px auto;}
	.img1{
	    width: 100px;
		height: 100px;
	    background: url('~@/../static/images/logo1.png') center center no-repeat;
	    background-size: 100px auto;
	}
	.img2{
		width: 100px;
	    height: 100px;
	    background-position: center center;
	    background-repeat:  no-repeat;
	    background-size: 100px auto;
	}
</style>

<div :style="{backgroundImage: 'url(https://cn.vuejs.org/images/logo.png)', width: '400px', height: '400px'}">foo</div>