if (!HttpContext.Current.Request.ContentType.ToLower().StartsWith("multipart/form-data")) return;        IServiceProvider objIProvider = (IServiceProvider)HttpContext.Current;
        HttpWorkerRequest wr =(HttpWorkerRequest) objIProvider.GetService(typeof(HttpWorkerRequest));
        if (!wr.HasEntityBody()) return;
        
        long lngTotalLength = Convert.ToInt64(wr.GetKnownRequestHeader(11));        //这里已经获得上传文件的大小,但却停不下来上传进程,过路的高人请指点迷津