WebRequest和WebClient

今天在办公室中无意间听见有人在唬啷【webrequest】和【webclient】,让我想起之前做的采集工具中的应用。

webrequest应用代码：【主要是用在采集信息之用】

 

        public static string GetAllResponseContent(string url, Encoding encode,string postdate)
        {
            try
            {
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);

                request.UserAgent = "Baiduspider(http://www.baidu.com/search/spider.htm)";
                //request.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.01; Windows NT 5.0)";
                request.Timeout = 10000;

                #region 填充要post的内容

                if (postdate.Length > 0)
                {
                    request.ContentType = "application/x-www-form-urlencoded";

                    request.Method = "Post";
                    byte[] data = encode.GetBytes(postdate);
                    request.ContentLength = data.Length;

                    Stream requestStream = request.GetRequestStream();

                    requestStream.Write(data, 0, data.Length);

                    requestStream.Close();
                }
                #endregion

                HttpWebResponse response = request.GetResponse() as HttpWebResponse;


                Stream stream;
                if (response.ContentEncoding == "gzip") // 注意内容编码
                {
                    stream = new GZipStream(response.GetResponseStream(), CompressionMode.Decompress);
                }
                else
                {
                    stream = response.GetResponseStream();
                }


                StreamReader reader = new StreamReader(stream, encode);
                string text = reader.ReadToEnd();
                reader.Close();
                response.Close();
                return text;

            }
            catch (Exception ex)
            {
                LogHelper.WriteException(string.Format(" 采集过程出现异常，追踪地址：{0}?{1}", url, postdate), ex);
            }
            return string.Empty;
        }

 

webclient应用代码：【主要是用在采集到信息后下载之用】

 

        /// <summary>
        /// 下载某站点的图片到本地服务器
        /// </summary>
        /// <param name="imgURI">图片源HTTP地址</param>
        /// <param name="imgFileName">图片名称</param>
        /// <returns></returns>
        private string DownLoadURIToLocal(string imgURI, string imgFileName)
        {
            string DownFileName = string.Format(ServerMapthPath, imgFileName);
            DownFileName = Server.MapPath(DownFileName);
            try
            {
                WebClient webClient = new WebClient();
                webClient.DownloadFile(imgURI, DownFileName);
            }
            catch (Exception ex)
            {
                string msg = ex.Message;
                return null;
            }
            return DownFileName;
        }