js上传图片预览

最新推荐文章于 2024-06-06 10:36:09 发布

转载最新推荐文章于 2024-06-06 10:36:09 发布 · 1.1w 阅读

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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
	<input type=file name="doc" id="doc" onchange="javascript:setImagePreview();">
	<p><div id="localImag"><img id="preview" width=-1 height=-1 style="diplay:none" /></div></p>
<script>
function setImagePreview() {
	var docObj=document.getElementById("doc");
	var imgObjPreview=document.getElementById("preview");
	if(docObj.files && docObj.files[0]){
		//火狐下，直接设img属性
		imgObjPreview.style.display = 'block';
		imgObjPreview.style.width = '300px';
		imgObjPreview.style.height = '120px';                    
		//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("localImag");
		//必须设置初始大小
		localImagId.style.width = "300px";
		localImagId.style.height = "120px";
		//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>
</body>
</html>