←Select platform

ChannelFields Class

Summary
Defines all of the fields for working with channels and sessions.

Syntax
C#
C++/CLI
Python
public class ChannelFields 
public ref class ChannelFields  
class ChannelFields: 
Remarks

When a client request is received, this class will contain the JPIP channel fields received from the client.

Access this class from the RequestFields.RequestChannelFields property in the RequestFields class when a new client request is received.

A JPIP client uses this class to construct a session with the server. A session will allow the server to maintain a client cache model. The cache model will contain information about the data sent to the client so as not to return these information in future requests unless otherwise specified by the CacheManagementFields.

If the client does not want to create a session with the server the channel fields should not be used. However, the client can always update the server cache model in session-based or stateless requests using the CacheManagementFields.

Example
C#
using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Jpip; 
using Leadtools.Jpip.Caching; 
using Leadtools.Jpip.HttpServer; 
using Leadtools.Jpip.RequestDecoder; 
using Leadtools.Jpip.RequestEncoder; 
using Leadtools.Jpip.Client.WinForms; 
using Leadtools.Jpip.Client.InteractiveDecoder; 
using Leadtools.Jpip.Server; 
using Leadtools.Jpip.Logging; 
 
public void SendClientRequest() 
{ 
   Leadtools.Examples.Support.SetLicense(); 
   RequestFields fields = new RequestFields(); 
   ModelItem cacheModleItem; 
   ExplicitBinDescriptor binDescriptor; 
   ModelElement cacheModleElement; 
 
   fields.RequestTargetFields = new TargetFields("0", "image1.jp2", null); 
   fields.RequestChannelFields.NewChannel = new string[] { "http" }; 
   fields.RequestDataLimitFields.DataLength = 16384; 
   cacheModleItem = new ModelItem(); 
   binDescriptor = new ExplicitBinDescriptor(ExplicitBin.MetaBin, 0, null); //indicate that metadata bin 0 is locally cached and need not be sent. 
   cacheModleElement = new ModelElement(false, binDescriptor); 
   cacheModleItem.BinDescriptors.Add(cacheModleElement); 
   cacheModleItem.CodeStreamRange.Add(new Range(0, 0)); 
   fields.RequestCacheManagementFields.ModelItems.Add(cacheModleItem); 
   ImageReturnType imageType = new ImageReturnType(ImageTypes.JppStream, false); 
   fields.RequestServerControlFields.ImageReturnTypes = new ImageReturnType[] { imageType }; 
   fields.RequestViewWindowFields.FrameSize = new LeadSize(500, 300); 
   fields.RequestViewWindowFields.RegionOffset = new LeadPoint(0, 100); 
   fields.RequestViewWindowFields.FrameSizeRoundingDirection = RoundingDirection.Closest; 
   SampleRange codeStreamRange = new SampleRange(); 
   codeStreamRange.Range = new Range(0, 0); 
   fields.RequestViewWindowFields.CodeStream.Add(codeStreamRange); 
   HttpRequestEncoder encoder = new HttpRequestEncoder(IPAddress.Parse("127.0.0.1"), 108); 
   HttpWebRequest request = encoder.Encode(fields, "jpip", null); 
   Console.WriteLine(request.Address.ToString()); 
   HttpWebResponse response = (HttpWebResponse)request.GetResponse(); 
   Console.WriteLine("Server response received."); 
   Console.WriteLine(response.Headers.ToString()); 
} 
 
public Socket GetClientSocket() 
{ 
   Socket listenSocket = new Socket(AddressFamily.InterNetwork, 
                                     SocketType.Stream, 
                                     ProtocolType.Tcp); 
   IPAddress hostIP = IPAddress.Parse("127.0.0.1"); 
   int port = 107; 
   IPEndPoint ep = new IPEndPoint(hostIP, port); 
   listenSocket.Bind(ep); 
   // start listening 
   listenSocket.Listen(10); 
   //a client should send a request to the listening address 
   Socket client = listenSocket.Accept(); 
   listenSocket.Close(); 
   return client; 
} 
Requirements

Target Platforms

Help Version 22.0.2023.3.31
Products | Support | Contact Us | Intellectual Property Notices
© 1991-2023 LEAD Technologies, Inc. All Rights Reserved.

Leadtools.Jpip Assembly

Products | Support | Contact Us | Intellectual Property Notices
© 1991-2023 LEAD Technologies, Inc. All Rights Reserved.