<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
*{
margin: 0;
padding: 0;
list-style: none;
}
html{
font-size: 62.5%;
}
body{
text-align: center;
}
.alert{
padding-top:60px;
font-size: 2.4rem;
display: none;
}
.container{
height: 100vh;
background-color: deepskyblue;
overflow: hidden;
}
@media screen and (min-width:968px){
/* 非移动端 */
.alert{
display: block;
}
.container{
display: none;
}
}
.head_pic{
width: 100px;
height: 100px;
margin: 80px auto;
background-image: url(https://img2.baidu.com/it/u=1814268193,3619863984&fm=253&app=138&size=w931&n=0&f=JPEG&fmt=auto?sec=1663174800&t=fe61fc5006e51309ba1186376f8c02ea);
background-size: cover ;
background-position: center center;
border-radius: 50%;
}
input{
display: block;
width: 100px;
height: 100px;
opacity: 0;
}
</style>
</head>
<body>
<p class="alert">请使用移动端打开</p>
<div class="container">
<div class="head_pic">
<input type="file">
</div>
</div>
</body>
<script>
var ipt=document.querySelector('input')
var dHeadPic=document.querySelector(".head_pic")
ipt.οnchange=function(){
// 选择的图片
var file=this.files[0];
// 创建一个文件读取对象
var reader=new FileReader()
reader.οnlοad=function(){
// 读取完成后执行
// reader.result //读取文件的信息内容
dHeadPic.style.backgroundImage=`url(${reader.result})`
}
reader.readAsDataURL(file)
}
</script>
</html>