C# 从服务器下载文件

        /// <summary>
        /// 下载文件 ———— 软件更新包
        /// </summary>
        /// <param name="URL">下载文件地址</param>
        /// <param name="filename">存放地址</param>
        /// <returns></returns>
        public bool DownloadFile(string URL, string filename)
        {
            float percent = 0;
            try
            {
                //
                HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(URL);
                //返回来自Internet资源的相应
                HttpWebResponse response = (HttpWebResponse)request.GetResponse();
                //获取请求返回的内容的长度
                long totalBytes = response.ContentLength;
                //进度条最大值
                progressBar.Maximun = (int)totalBytes ;
                //获取流，该流用于读取来自服务器的响应的体。
                Stream resposeStream = response.GetResponseStream();
                //指定位置创建文件夹