web service notes

1. 性能提高
   压缩传输数据, 减少多次调用, XML解析器的优化和选择, 简化标签, 缓存机制
   ref: http://www.ibm.com/developerworks/cn/webservices/0710_wangyun/index.html?S_TACT=105AGX52&S_CMP=NL&ca=dnl-cn-11212007
2. in class library project use  WebServiceHandlerFactory to create Web service, http://www.codeproject.com/useritems/wsinaclasslibrary.asp
   write a class WebServiceBase to implements webserviceHandlerFactory, then implement your web service inherit from this class, and copy this compoment into your web app bin directory, then add <add path="WSTest.asmx" verb="*" type="WSLibrary.WSTest" validate="false"/> into your web.config's httphandler section.
3. [WebMethod(EnableSession=true)]XXX 此声明可以在WS中引用session对象, 某种程度上可以提高性能; 但需要客户端在调用时支持,默认情况下browser中调用WS时要有SESSION的,而在普通的EXE或程序中调用WS时,需要显示声明要使用cookie,否则服务器端的session无效..net 中声明如下:
   WebService1 srv = new WebService1();
   srv.CookieContainer = new CookieContainer();
   只有经过这样声明,调用的WS才会传递SESSIONID,建立在一个应用中只有一个地方可获取WS,即采用singleton模式,这样所有地方调用WS时都有sessionID支持.
4. 利用WS上传文件,可以在CLIENT中将文件中的内容读取到byte[]中,然后调用WS接口,然后WS再将byte写入到文件中
   转换FileStream fileStream = File.OpenRead(path + fileName);为MemoryStream,再转换为byte[].
   public byte[] ConvertStreamToByteBuffer(System.IO.Stream theStream)
           {
               int b1;
               System.IO.MemoryStream tempStream = new System.IO.MemoryStream();
               while ((b1 = theStream.ReadByte()) != -1)
               {
                   tempStream.WriteByte(((byte)b1));
               }
               return tempStream.ToArray();
           }
   如果是将byte[]写入到文件,则代码如下:
   {
                   MemoryStream memoryStream = new MemoryStream(fs);
                   FileStream fileStream = new FileStream(path + fileName, FileMode.Create);
                   memoryStream.WriteTo(fileStream);
                   memoryStream.Close();
                   fileStream.Close();
                   fileStream = null;
                   memoryStream = null;