C# 结合html5 批量上传文件和图片预览

html5 新特性 <input id="imgsf" type="file" name="imgsf" multiple />input file 中增加 multiple 属性可以选择多文件。IE9以下版本不兼容 <form id="form1" method="post" action="upload_json.ashx" enctype="multipart/form-data">
<div>
<input id="imgsf" type="file" name="imgsf" multiple />
<input type="text" name="ceshi" value="panlitao" >
<input type="submit" value="提交" />
</div>
</form>//预览js <div id="imgrq">
</div>
<script type="text/javascript"> $("#imgsf").change(function () {
var filedx = 0;
for (var i = 0, j = this.files.length; i < j; i++) {
$("#imgrq").append("<img src=\"" + window.URL.createObjectURL(this.files[i]) + "\" width=\"100\" height=\"100\" />");
} }); </script>C# 代码 public class upload_json : IHttpHandler
{
// private HttpContext context; public void ProcessRequest(HttpContext context)
{
String aspxUrl = context.Request.Path.Substring(0, context.Request.Path.LastIndexOf("/") + 1); //文件保存目录路径
String savePath = "attached/"; //文件保存目录URL
String saveUrl = aspxUrl + "attached/"; //定义允许上传的文件扩展名
Hashtable extTable = new Hashtable();
extTable.Add("image", "gif,jpg,jpeg,png,bmp");
//extTable.Add("flash", "swf,flv");
//extTable.Add("media", "swf,flv,mp3,wav,wma,wmv,mid,avi,mpg,asf,rm,rmvb");
//extTable.Add("file", "doc,docx,xls,xlsx,ppt,htm,html,txt,zip,rar,gz,bz2"); //最大文件大小
int maxSize = 1000000;
// this.context = context;
String newFileName = "";
for (int i = 0; i < context.Request.Files.Count;i++ )
{
HttpPostedFile imgFile = context.Request.Files[i]; if (imgFile == null)
{
showError("请选择文件。");
} String dirPath = context.Server.MapPath(savePath);
if (!Directory.Exists(dirPath))
{
showError("上传目录不存在。");
} String dirName = context.Request.QueryString["dir"];
if (String.IsNullOrEmpty(dirName))
{
dirName = "image";
}
if (!extTable.ContainsKey(dirName))
{
showError("目录名不正确。");
} String fileName = imgFile.FileName;
String fileExt = Path.GetExtension(fileName).ToLower(); if (imgFile.InputStream == null || imgFile.InputStream.Length > maxSize)
{
showError("上传文件大小超过限制。");
} //修改为文件流去判断文件格式
// string exPath = mall_bll.Common.isfilltype(stream: imgFile.InputStream).ToLower(); // if (exPath != "jpg" && exPath != "gif" && exPath != "bmp" && exPath != "png")
// { showError("上传文件扩展名是不允许的扩展名。\n只允许" + ((String)extTable[dirName]) + "格式。"); } //if (String.IsNullOrEmpty(fileExt) || Array.IndexOf(((String)extTable[dirName]).Split(','), fileExt.Substring(1).ToLower()) == -1)
//{
// showError("上传文件扩展名是不允许的扩展名。\n只允许" + ((String)extTable[dirName]) + "格式。");
//} //创建文件夹
dirPath += dirName + "/";
saveUrl += dirName + "/";
if (!Directory.Exists(dirPath))
{
Directory.CreateDirectory(dirPath);
}
String ymd = DateTime.Now.ToString("yyyyMMdd", DateTimeFormatInfo.InvariantInfo);
dirPath += ymd + "/";
saveUrl += ymd + "/";
if (!Directory.Exists(dirPath))
{
Directory.CreateDirectory(dirPath);
} newFileName = DateTime.Now.ToString("yyyyMMddHHmmss_ffff", DateTimeFormatInfo.InvariantInfo) + fileExt;
String filePath = dirPath + newFileName; imgFile.SaveAs(filePath);
}
String fileUrl = saveUrl + newFileName; Hashtable hash = new Hashtable();
hash["error"] = 0;
hash["url"] = fileUrl;
context.Response.AddHeader("Content-Type", "text/html; charset=UTF-8");
// context.Response.Write(JsonMapper.ToJson(hash));
context.Response.End();
} private void showError(string message)
{
Hashtable hash = new Hashtable();
hash["error"] = 1;
hash["message"] = message;
// context.Response.AddHeader("Content-Type", "text/html; charset=UTF-8");
// context.Response.Write(JsonMapper.ToJson(hash));
// context.Response.End();
} public bool IsReusable
{
get
{
return true;
}
}
}