图片自适应DIV盒子的大小
img{width: auto;height: auto;max-height: 100%;max-width: 100%;}
根据浏览器窗口大小,自动更改图片大小
<img ref="img" :style="{width: myWidth,height:'myHeight'}" :src="myImgData[index]" >
data(){return{myWidth:'100%',myHeight:'auto',imgHeight:""}},
watch:{imgHeight(){if(this.imgHeight>775){this.myHeight = "775px"this.myWidth = "auto"}}},