Reinvite

If you want to change characteristics of an existing session then you can call Invite method again with Dialog as parameter. Invite sent for an existing dialog references the same Call-ID as the original Invite and contains the same "To" and "From" tags.

C# example

using System;
using Independentsoft.Sip;
using Independentsoft.Sip.Sdp;
using Independentsoft.Sip.Methods;

namespace Sample
{
    class Program
    {
        private static Logger logger;
        private static SipClient client;

        public static void Main(string[] args)
        {
            client = new SipClient("sipdomain.com", "Bob", "password");

            logger = new Logger();
            logger.WriteLog += new WriteLogEventHandler(OnWriteLog);
            client.Logger = logger;

            client.ReceiveRequest += new ReceiveRequestEventHandler(OnReceiveRequest);
            client.ReceiveResponse += new ReceiveResponseEventHandler(OnReceiveResponse);

            client.Connect();

            SessionDescription session = new SessionDescription();
            session.Version = 0;

            Owner owner = new Owner();
            owner.Username = "Bob";
            owner.SessionID = 16264;
            owner.Version = 18299;
            owner.Address = "192.168.0.1";

            session.Owner = owner;
            session.Name = "SIP Call";

            Connection connection = new Connection();
            connection.Address = "192.168.0.1";

            session.Connection = connection;

            Time time = new Time(0, 0);
            session.Time.Add(time);

            Media media1 = new Media();
            media1.Type = "audio";
            media1.Port = 25282;
            media1.TransportProtocol = "RTP/AVP";
            media1.MediaFormats.Add("0");
            media1.MediaFormats.Add("101");

            media1.Attributes.Add("rtpmap", "0 pcmu/8000");
            media1.Attributes.Add("rtpmap", "101 telephone-event/8000");
            media1.Attributes.Add("fmtp", "101 0-11");

            session.Media.Add(media1);

            RequestResponse inviteRequestResponse = client.Invite("sip:Bob@mydomain.com", "sip:Alice@mydomain.com", "sip:Bob@" + client.LocalIPEndPoint.ToString(), session);
            client.Ack(inviteRequestResponse);

            Dialog phoneCallDialog = client.GetDialog(inviteRequestResponse);

            Console.WriteLine("Press ENTER to modify session and re-invite to session.");
            Console.Read();

            session.Media.Remove(media1);
            media1.Port = 25283;
            session.Media.Add(media1);

            RequestResponse inviteRequestResponse2 = client.Invite(phoneCallDialog, session);
            client.Ack(inviteRequestResponse2);

            Console.WriteLine("Press ENTER to exit.");
            Console.Read();
            Console.Read();
            client.Disconnect();
        }

        private static void OnReceiveRequest(object sender, RequestEventArgs e)
        {
            client.AcceptRequest(e.Request);
        }

        private static void OnReceiveResponse(object sender, ResponseEventArgs e)
        {
        }

        private static void OnWriteLog(object sender, WriteLogEventArgs e)
        {
            Console.Write(e.Log);
        }
    }
}

VB example

Imports System
Imports Independentsoft.Sip
Imports Independentsoft.Sip.Sdp
Imports Independentsoft.Sip.Methods

Module Module1
    Private logger As Logger
    Private client As SipClient

    Public Sub Main(ByVal args() As String)

        client = New SipClient("sipdomain.com", "Bob", "password")

        logger = New Logger
        AddHandler logger.WriteLog, AddressOf OnWriteLog
        client.Logger = logger

        AddHandler client.ReceiveRequest, AddressOf OnReceiveRequest
        AddHandler client.ReceiveResponse, AddressOf OnReceiveResponse

        client.Connect()

        Dim session As SessionDescription = New SessionDescription
        session.Version = 0

        Dim owner As Owner = New Owner
        owner.Username = "Bob"
        owner.SessionID = 16264
        owner.Version = 18299
        owner.Address = "192.168.0.1"

        session.Owner = owner
        session.Name = "SIP Call"

        Dim connection As Connection = New Connection
        connection.Address = "192.168.0.1"

        session.Connection = connection

        Dim time As Time = New Time(0, 0)
        session.Time.Add(time)

        Dim media1 As Media = New Media
        media1.Type = "audio"
        media1.Port = 25282
        media1.TransportProtocol = "RTP/AVP"
        media1.MediaFormats.Add("0")
        media1.MediaFormats.Add("101")

        media1.Attributes.Add("rtpmap", "0 pcmu/8000")
        media1.Attributes.Add("rtpmap", "101 telephone-event/8000")
        media1.Attributes.Add("fmtp", "101 0-11")

        session.Media.Add(media1)

        Dim inviteRequestResponse As RequestResponse = client.Invite("sip:Bob@mydomain.com", "sip:Alice@mydomain.com", "sip:Bob" + client.LocalIPEndPoint.ToString(), session)
        client.Ack(inviteRequestResponse)

        Dim phoneCallDialog As Dialog = client.GetDialog(inviteRequestResponse)

        Console.WriteLine("Press ENTER to modify session and re-invite to session.")
        Console.Read()

        session.Media.Remove(media1)
        media1.Port = 25283
        session.Media.Add(media1)

        Dim inviteRequestResponse2 As RequestResponse = client.Invite(phoneCallDialog, session)
        client.Ack(inviteRequestResponse2)

        Console.WriteLine("Press ENTER to exit.")
        Console.Read()
        Console.Read()
        client.Disconnect()

    End Sub

    Private Sub OnReceiveRequest(ByVal sender As Object, ByVal e As RequestEventArgs)
        client.AcceptRequest(e.Request)
    End Sub

    Private Sub OnReceiveResponse(ByVal sender As Object, ByVal e As ResponseEventArgs)
    End Sub

    Private Sub OnWriteLog(ByVal sender As Object, ByVal e As WriteLogEventArgs)
        Console.Write(e.Log)
    End Sub

End Module

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SIP .NET > Tutorial > Reinvite

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