SharePoint 2010 编程上传文档

protected void btnUpload_Click(object sender, EventArgs e)
        {
            Boolean FileOK = false;
            Boolean FileSaved = false;
            String accountName = SPContext.Current.Web.CurrentUser.LoginName;
            string fileNameWithoutExtension = GetFileNameFromAccountName(accountName);
            String FileExtension = string.Empty;

            SPWeb web = SPContext.Current.Web;

            SPSecurity.RunWithElevatedPrivileges(delegate()
            {
                    using (SPSite currentSite = new SPSite(web.Site.Url))
                    {             
                        using (SPWeb currentWeb = currentSite.OpenWeb())
                        {

                            if (Upload.HasFile)
                            {
                                    FileExtension = Path.GetExtension(Upload.FileName.ToString()).ToLower();
                                    String[] allowedExtensions = { ".png", ".jpeg", ".jpg", ".gif" };
                                    for (int i = 0; i < allowedExtensions.Length; i++)
                                    {
                                            if (FileExtension == allowedExtensions[i])
                                            {
                                                    FileOK = true;
                                                    break;
                                            }
                                    }
                                }

                            if (FileOK)
                            {
                                    try
                                    {

                                            currentWeb.AllowUnsafeUpdates = true;
                                            SPSecurity.CatchAccessDeniedException = false;

                                            SPList listePictureUpload = currentWeb.GetList(SPUtility.ConcatUrls(currentWeb.Url, "User Photos"));
                                            SPFile itemPictureUpload = currentWeb.Files.Add(listePictureUpload.RootFolder.Url + "/" + Upload.FileName.Remove(Upload.FileName.Length -                                 FileExtension.Length) + fileNameWithoutExtension + FileExtension, Upload.FileBytes, true);
                                            //SPFile itemPictureUpload = listePictureUpload.RootFolder.Files.Add(Upload.FileName.Remove(Upload.FileName.Length - FileExtension.Length) +                                 fileNameWithoutExtension + FileExtension, Upload.FileBytes, true);
                                            currentWeb.AllowUnsafeUpdates = false;
                                    }
                             }
                      }
                }
    
         });

}