enctype="multipart/form-data"表单上传文件

  <form method="post" enctype="multipart/form-data" action="Default2.aspx">

    <div>

    <input type="file" name="img" /><input type="submit"  value="提交" /></div>

    </form>

 

 

 protected void Page_Load(object sender, EventArgs e)

        {

            HttpFileCollection files = Request.Files;

            string fileDestination = string.Empty;

            if (files.Count > 0)

            {

                HttpPostedFile postedFile = Request.Files[0];

                string fileName = Path.GetFileName(postedFile.FileName);

                if (fileName != "")

                {

                    SaveFile(postedFile, "IMAGE");

                    Response.Write("upload succes!");

                }

            }

        }

        public string SaveFile(HttpPostedFile postedFile, string postType)

        {

            string UploadFileName = DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString() + DateTime.Now.Day.ToString() + DateTime.Now.Hour.ToString() + DateTime.Now.Minute.ToString() + DateTime.Now.Millisecond.ToString();

            string extension = Path.GetFileName(postedFile.FileName);

            string strFileName = HttpContext.Current.Request.ApplicationPath + "//UpLoadFile//" + postType + "//" + System.DateTime.Today.Year.ToString() + "//" + System.DateTime.Today.Month.ToString() + "//";

            string root = System.Web.HttpContext.Current.Server.MapPath(strFileName);

            string destination = System.Web.HttpContext.Current.Server.MapPath(strFileName) + UploadFileName + extension;

            string path = "/UpLoadFile/" + postType + "/" + System.DateTime.Today.Year.ToString() + "/" + System.DateTime.Today.Month.ToString() + "/" + UploadFileName + extension;

            if (!Directory.Exists(root))

            {

                Directory.CreateDirectory(root);

            }

            postedFile.SaveAs(destination);

            return path;

        }