/// <summary>
        /// 仅请求远程数据
        /// 当收到回应时,立即中止
        /// </summary>
        /// <param name="url"></param>
        public static void RequestOnly(string url)
        {
            AsyncRemoteRequest arq = new AsyncRemoteRequest();

            arq._url = url;

            ThreadPool.QueueUserWorkItem(arq.RequestOnly, arq);
        }
        /// <summary>
        /// 仅请求远程数据(POST)
        /// 当收到回应时,立即中止
        /// </summary>
        /// <param name="url"></param>
        public static void RequestOnly(string url, byte[] postData)
        {
            AsyncRemoteRequest arq = new AsyncRemoteRequest();

            arq._url      = url;
            arq._postData = postData;

            ThreadPool.QueueUserWorkItem(arq.RequestOnly, arq);
        }
        /// <summary>
        /// 异步下载远程文件
        /// </summary>
        /// <param name="url"></param>
        /// <param name="file">保存到文件(绝对路径)</param>
        public static void DownloadFile(string url, string file)
        {
            AsyncRemoteRequest arq = new AsyncRemoteRequest();

            arq._url    = url;
            arq._toFile = file;

            ThreadPool.QueueUserWorkItem(arq.DownloadFile, arq);
        }