@{
 ViewData["Title"] = "Home Page";
 Layout = null;
}
<script src="~/jQuery.1.9.0/Content/Scripts/jquery-1.9.0.js"></script>
<script src="~/bootstrap.3.3.0/content/Scripts/bootstrap.js"></script>
<link rel="stylesheet" href="~/bootstrap.3.3.0/content/Content/bootstrap.css" rel="external nofollow" >
<script type="text/javascript" src="~/bootstrap-fileinput.4.3.8/content/Scripts/fileinput.js"></script>
<script type="text/javascript" src="~/bootstrap-fileinput.4.3.8/content/Scripts/locales/zh.js"></script>
<link rel="stylesheet" href="~/bootstrap-fileinput.4.3.8/content/Content/bootstrap-fileinput/css/fileinput.css" rel="external nofollow" >
 <script type="text/javascript">
  $(function () {
   var control = $("#txt_file");
   var uploadrul = "/Home/UploadFile";
   control.fileinput({
    language: ''zh'', //设置语言
    uploadUrl: uploadrul, //上传的地址
    allowedFileExtensions: [''png''],//接收的文件后缀
    showUpload: true, //显示批量上传按钮
    showCaption: false,//是否显示标题
    browseClass: "btn btn-primary", //按钮样式  
    dropZoneEnabled: true,//是否显示拖拽区域
    //minImageWidth: 50, //图片的最小宽度
    //minImageHeight: 50,//图片的最小高度
    //maxImageWidth: 1000,//图片的最大宽度
    //maxImageHeight: 1000,//图片的最大高度
    //maxFileSize: 0,//单位为kb，如果为0表示不限制文件大小
    //minFileCount: 0,
    maxFileCount: 100,
    enctype: ''multipart/form-data'',
    validateInitialCount: true,
    previewFileIcon: "<iglyphicon glyphicon-king''></i>",
    msgFilesTooMany: "选择上传的文件数量({n}) 超过允许的最大数值{m}！",
   });
   //导入文件上传完成之后的事件
   $("#txt_file").on("fileuploaded", function (event, data, previewId, index) {
   });
  });
 </script>
</table>
 <div> 
  <form>
   <div>
    <div>
     <h4id="myModalLabel">请选择xml文件</h4>
    </div>
    <div>
     <input type="file" name="txt_file" id="txt_file" multiple/>
    </div>
   </div>
  </form>
 </div>

public JsonResult UploadFile()
  {
   uploadResult result = new uploadResult();
   try
   {
    var oFile = Request.Form.Files["txt_file"];
    Stream sm=oFile.OpenReadStream();
    result.fileName = oFile.FileName;
    if(!Directory.Exists(AppContext.BaseDirectory+"/Image/"))
    {
     Directory.CreateDirectory(AppContext.BaseDirectory+"/Image/");
    }
    string filename=AppContext.BaseDirectory+"/Image/" + DateTime.Now.ToString("yyyymmddhhMMssss")+Guid.NewGuid().ToString() + ".png";
    FileStream fs=new FileStream(filename,FileMode.Create);
    byte[] buffer =new byte[sm.Length];
    sm.Read(buffer,0,buffer.Length);
    fs.Write(buffer,0,buffer.Length);
    fs.Dispose();
   }
   catch(Exception ex)
   {
    result.error = ex.Message;
   }
   return Json(result);
  }
  public class uploadResult
  {
   public string fileName { get; set; }
   public string error { get; set; }
  }

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