无刷新预览所选择的图片示例代码

2013年11月30日作者：
代码如下
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 
<title>无标题文档</title> 
<script type="text/javascript"> 
//本地图片预览 
function setImagePreview(fieldupload, image, imagediv) { 
var docObj = document.getElementById(fieldupload); 
var imgObjPreview = document.getElementById(image); 
if (docObj.files && docObj.files[0]) { 
//火狐下，直接设img属性 
imgObjPreview.style.display = 'block'; 
imgObjPreview.style.width = '150px'; 
imgObjPreview.style.height = '150px'; 
//imgObjPreview.src = docObj.files[0].getAsDataURL(); 
//火狐7以上版本不能用上面的getAsDataURL()方式获取，需要一下方式 
imgObjPreview.src = window.URL.createObjectURL(docObj.files[0]); 
} else { 
//IE下，使用滤镜 
docObj.select(); 
var imgSrc = document.selection.createRange().text; 
var localImagId = document.getElementById(imagediv); 
//必须设置初始大小 
localImagId.style.width = "150px"; 
localImagId.style.height = "150px"; 
//图片异常的捕捉，防止用户修改后缀来伪造图片 
try { 
localImagId.style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale)"; localImagId.filters.item("DXImageTransform.Microsoft.AlphaImageLoader").src = imgSrc; 
} catch (e) { 
alert("您上传的图片格式不正确，请重新选择!"); 
return false; 
} 
imgObjPreview.style.display = 'none'; 
document.selection.empty(); 
} 
return true; 
} 
</script> 
</head> 

<body> 
<div id="localImag"> <img id="preview" width="150px" height="150px" src="http://images.cnblogs.com/cnblogs_com/yc-755909659/559257/o_%e6%9a%82%e6%97%a0%e5%9b%be%e7%89%87.gif" alt="" /></div> 
<div> 
<input type="file" onchange="javascript:setImagePreview('upload','preview','localImag');" id="upload" /> 
</div> 
</body> 
</html>