一个手写的vue放大镜效果

import mirror from 'xx/mirror' export default {  components:{   mirror  },  data(){   return {    width:300,    picList:[      xxxxxx,      xxxxxx    ],   }  } }

<mirror :width="width" :picList="picList" />  

<template> <div class="mirror">   <div class="wrap" :style="{width:width+'px',height:width+'px'}" >    <div ref="truth" :style="{width:'100%',height:'100%'}" @mousemove="move" @mouseenter="showMagnify" @mouseleave="hideMagnify">    <div class="mask" ref="mask" v-show = "showMask" :style="{width:width/2+'px',height:width/2+'px',left:maskPosition.x+'px',top:maskPosition.y+'px'}"></div>    <img :src="picList[picIndex]" draggable="false"/>    </div>    <div class="virtual" ref="virtual" v-if = "isShowVirtual" :style="{width:width+'px',height:width+'px'}" >      <div class="big" ref = "bigPic" :style="{position:'absolute',width:2*width+'px',height:2*width+'px',backgroundSize:'100% 100%',backgroundImage:`url(${picList[picIndex]})`,left:percent.x, top:percent.y}" >      </div>    </div>   </div>   <ul class="picList" :style="{width:width+'px'}">     <li v-for = "(item,index) in picList" :class="{now:index==picIndex}" :data-index="index" :key ="item" @mouseenter="changeIndex">      <img :src ="item" />     </li>   </ul> </div></template>

 export default {   props:['width','picList'],//宽度是用来给放大镜的   data(){    return {     picIndex:0,     isShowVirtual:false,     showMask:false,     maskPosition:{},     percent:{},    }   },   methods:{    computedOffset(obj,prop){ //计算元素到body的绝对位置    if(obj==document.body || obj.offsetParent == document.body){     return parseInt(obj[prop])    }    return parseInt(obj[prop])+this.computedOffset(obj.offsetParent,prop)  },    changeIndex(e){     this.picIndex = e.target.dataset.index    },    showMagnify(e){     this.showMask=true;     this.isShowVirtual = true;    },    hideMagnify(){     this.isShowVirtual=false;     this.showMask=false    },    computePosition(e){      let x = e.pageX,y = e.pageY;      let mask = this.$refs.mask;      let truth = this.$refs.truth;      let virtual = this.$refs.virtual;      let bigPic = this.$refs.bigPic;      x = x-this.computedOffset(truth,'offsetLeft') -mask.offsetWidth/2;      y = y-this.computedOffset(truth,'offsetTop')- mask.offsetHeight/2;     if(x<=0) {       x=0      }else if(x>truth.offsetWidth - mask.offsetWidth){       x = truth.offsetWidth/2      }      if(y<=0){       y=0;      }      else if(y>truth.offsetHeight - mask.offsetHeight){       y = truth.offsetHeight/2      }      this.maskPosition = {       x,y      }      //计算比例      this.percent={       x:-x/(truth.offsetWidth-mask.offsetWidth)*(bigPic.offsetWidth - virtual.offsetWidth)+'px',       y:-y/(truth.offsetHeight-mask.offsetHeight)*(bigPic.offsetHeight - virtual.offsetHeight)+'px'      }    },    move(e){     this.computePosition(e)    }  }  }

<style lang="less" scoped>.now{ border-color: cyan !important;} .mirror{  width:100%;  .wrap{   user-select: none;   margin-bottom: 20px;   position: relative;   background-color: #fff;   border:1px solid gray;   box-sizing:border-box;     cursor: pointer;    img{     width:100%;     height:100%;    }    .virtual{     overflow:hidden;     width:100%;     height:100%;     position:absolute;     left:calc(100% + 10px);     top:0;     background-repeat:no-repeat    }    .mask{     position: absolute;     background-image: url('https://img-tmdetail.alicdn.com/tps/i4/T12pdtXaldXXXXXXXX-2-2.png');     background-repeat:repeat;     cursor: move;    }  }  .picList{   width:100%;   display: flex;   justify-content: space-between;   flex-wrap:wrap;   li{    width:50px;    height:50px;    margin:5px;    border:1px solid transparent;    box-sizing: border-box;    img{     width:100%;     height:100%    }   }  }  .picList:after{   content:"";   flex:auto;  } }</style>