版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/u010861514/article/details/76325650
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<!-- <input type="file" id="file" onchange="showimg('file', 'img')"> -->
<!-- 或者 -->
<input type="file" id="file" onchange="showimg(this.id, 'img')">
<img src="" alt="" id="img">
</body>
</html>
<script>
/*
* 显示本地图片
* @param string sourceId input 按钮的id
* @param string targetId img 按钮的id
*/
function showimg(sourceId = 'file', targetId = 'img') {
if (typeof FileReader === 'undefined') {
alert('Your browser does not support FileReader...');
return;
}
var reader = new FileReader();
reader.onload = function(e) {
var img = document.getElementById(targetId);
img.src = reader.result;
}
reader.readAsDataURL(document.getElementById(sourceId).files[0]);
}
</script>