<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
<style type="text/css">
#preview, .img, img
{
width:200px;
height:200px;
}
#preview
{
border:1px solid #000;
}
</style>
</head>
<body>
<div id="preview"></div>
<input type="file" onchange="preview(this)" />
<script type="text/javascript">
function preview(file)
{
var prevDiv = document.getElementById(‘preview‘);
if (file.files && file.files[0])
{
var reader = new FileReader();
reader.onload = function(evt){
prevDiv.innerHTML = ‘<img src="‘ + evt.target.result + ‘" />‘;
}
reader.readAsDataURL(file.files[0]);
}
else
{
prevDiv.innerHTML = ‘<div class="img" style="filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale,src=\‘‘ + file.value + ‘\‘"></div>‘;
}
}
</script>
</body>
</html>
原文：http://www.cnblogs.com/wuwenshuai/p/7172163.html