ASP.NET 使用Get方式请求WebService，并得到DataSet结果

注意：如下使用了如下webservices的配置，将导致客户端引用时将无法引用到ArrayOfInt或ArrayOfString参数。

WebService有多种方式进行请求，如Get,Post,Soap,Documentation等等，注意要使用时在web.config中的system.web节点中增加类似如下的配置节点信息

    <webServices>
      <protocols>
        <add name="HttpGet"/>
        <add name="HttpPost"/>
        <add name="HttpSoap"/>        
        <add name="Documentation"/>
        <add name="HttpPostLocalhost"/>        
      </protocols>
    </webServices>

在WebService类中实现了如下方法，分别是返回byte[]和XmlDocument对象

       [WebMethod(Description = "返回byte数据")]
        public byte[] GetKeywordQueueToByteArray(string username, string clientId, string seType, string batchTotal, string maxPage)
        {
            DataSet ds = InitData();
            ds.DataSetName = "KeywordQueue";
            byte[] bytes = DataSetToByte(ds);
            //返回前可压缩，节省流量
            return bytes;
        }


        [WebMethod(Description = "返回XmlDocument")]
        public XmlDocument GetKeywordQueueToXml(string username, string clientId, string seType, int batchTotal, int maxPage)
        {
            XmlDocument xd = new XmlDocument();
            DataSet ds = InitData();
            ds.DataSetName = "KeywordQueue";
            xd.LoadXml(ds.GetXml());
            return xd;
        }

        private DataSet InitData()
        {
            DataSet dataset = new DataSet();
            DataTable dtKeyword = new DataTable();
            dtKeyword.TableName = "keywords";
            dtKeyword.Columns.AddRange(new DataColumn[]{
                new DataColumn() { ColumnName = "keyword", DataType = typeof(System.String) },
                new DataColumn() { ColumnName = "setype", DataType = typeof(System.String) },
                new DataColumn() { ColumnName = "maxpage", DataType = typeof(System.Int32) }
            });
            DataTable dtSeType = new DataTable();
            dtSeType.TableName = "se";
            dtSeType.Columns.AddRange(new DataColumn[]{
                new DataColumn() { ColumnName = "code", DataType = typeof(System.String) },
                new DataColumn() { ColumnName = "name", DataType = typeof(System.String) },
                new DataColumn() { ColumnName = "url", DataType = typeof(System.String) }
            });

            dtKeyword.Rows.Add("手机", "BD", 1);
            dtKeyword.Rows.Add("网络游戏", "BD", 1);
            dtSeType.Rows.Add("BD", "百度", "");
            dtSeType.Rows.Add("GG", "GG", "");

            dataset.Tables.Add(dtKeyword);
            dataset.Tables.Add(dtSeType);

            return dataset;
        }
        
        /// <summary>
        /// 把DateSet转化成byte 
        /// </summary>
        /// <param name="m_ds"></param>
        /// <returns></returns>
        public byte[] DataSetToByte(DataSet dataset)
        {
            byte[] result = null;
            MemoryStream memStream = new MemoryStream();
            IFormatter m_formatter = new BinaryFormatter();
            dataset.RemotingFormat = SerializationFormat.Binary;
            MemoryStream ms = new MemoryStream();
            IFormatter bf = new BinaryFormatter();
            bf.Serialize(ms, dataset);
            result = ms.ToArray();
            ms.Close();
            return result;
        }

请求WebService的测试方法

        public static void Invoke()
        {
            //string webserviceUrl = "http://localhost:9090/KeywordQueueService.asmx/HelloWorld?content=hello world";
            Console.WriteLine("WebService返回XmlDocument,直接解析为DataSet");
            GetDataSetFromWebServiceByXmlDocument();

            Console.WriteLine("WebService返回byte[],直接解析为DataSet");
            GetDataSetFromWebServiceByteArray();
        }

        /// <summary>
        /// WebService返回的是Byte数组
        /// </summary>
        static void GetDataSetFromWebServiceByteArray()
        {
            string webserviceUrl = "http://localhost:9090/KeywordQueueService.asmx/GetKeywordQueueToByteArray?username=test1&clientId=dkkad8789adda&seType=BD&batchTotal=61&maxPage=1";
            string charSet = "utf-8";

            try
            {
                string pageContent = GetWebServiceContent(webserviceUrl, charSet);
                Console.WriteLine(pageContent);
                //加载文档
                XmlDocument xd = new XmlDocument();
                xd.LoadXml(pageContent);
                byte[] bytes = Convert.FromBase64String(xd.DocumentElement.InnerText);
                //因为WebService方法中序列化过，所以这里需要反序列化
                MemoryStream ms = new MemoryStream(bytes);
                System.Runtime.Serialization.IFormatter bf = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
                object obj = bf.Deserialize(ms);
                DataSet dataset = obj as DataSet;
                ms.Close();
            }
            catch (Exception err)
            {
                Console.WriteLine(err.ToString());
            }
        }

        /// <summary>
        /// WebService返回的是XmlDocument
        /// </summary>
        static void GetDataSetFromWebServiceByXmlDocument()
        {
            string webserviceUrl = "http://localhost:9090/KeywordQueueService.asmx/GetKeywordQueueToXml?username=test1&clientId=dkkad8789adda&seType=BD&batchTotal=61&maxPage=1";
            string charSet = "utf-8";

            try
            {
                string pageContent = GetWebServiceContent(webserviceUrl, charSet);
                Console.WriteLine(pageContent);
                XmlDocument xd = new XmlDocument();
                xd.LoadXml(pageContent);
                DataSet ds = new DataSet();
                ds.ReadXml(new XmlNodeReader(xd));
            }
            catch (Exception err)
            {
                Console.WriteLine(err.ToString());
            }
        }

        /// <summary>
        /// 请求WebService
        /// </summary>
        /// <param name="webserviceUrl"></param>
        /// <param name="charset"></param>
        /// <returns></returns>
        static string GetWebServiceContent(string webserviceUrl, string charset)
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(webserviceUrl);
            request.Method = "GET";
            request.Timeout = 60000;
            HttpWebResponse response = request.GetResponse() as HttpWebResponse;
            Stream streamReceive = response.GetResponseStream();
            Encoding encoding = Encoding.Default;
            if (!string.IsNullOrEmpty(charset) && Encoding.GetEncoding(charset) != Encoding.Default)
            {
                encoding = Encoding.GetEncoding(charset);
            }

            StreamReader streamReader = new StreamReader(streamReceive, encoding);
            return streamReader.ReadToEnd();
        }

        /// <summary>
        /// 将Byte[]转换为DataSet
        /// <para>反序列化了一下</para>
        /// </summary>
        /// <param name="data"></param>
        /// <returns></returns>
        static DataSet GetDataSetByUnCompressByte(byte[] data)
        {
            MemoryStream ms = new MemoryStream(data);
            System.Runtime.Serialization.IFormatter bf = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
            object obj = bf.Deserialize(ms);
            DataSet dsResult = (DataSet)obj;
            ms.Close();
            return dsResult;
        }

 注意，如果数据量极少时，直接返回XmlDocument占用流量更小，如果数据量稍大，则使用压缩的byte[]方式更节省流量！