Cancel invitation

The Cancel method is used to terminate pending Invite requests.

C# example

using System;
using System.Threading;
using Independentsoft.Sip;
using Independentsoft.Sip.Sdp;

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

        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();

            Thread inviteThread = new Thread(new ThreadStart(Invite));
            inviteThread.Start();

            Thread.CurrentThread.Join(3000);
            inviteThread.Abort();

            //Wait 3 seconds and if there is no final response on Invite method then cancel.
            if (inviteRequestResponse == null)
            {
                client.Cancel();
            }

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

        private static void Invite()
        {
            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);

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

        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 System.Threading
Imports Independentsoft.Sip
Imports Independentsoft.Sip.Sdp

Module Module1
    Private logger As Logger
    Private client As SipClient
    Private inviteRequestResponse As RequestResponse

    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 inviteThread As New Thread(AddressOf Invite)
        inviteThread.Start()

        Thread.CurrentThread.Join(3000)
        inviteThread.Abort()

        'Wait 3 seconds and if there is no final response on Invite method then cancel.
        If inviteRequestResponse Is Nothing Then
            client.Cancel()
        End If

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

    End Sub

    Private Sub Invite()
        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)

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

Independentsoft

SIP .NET > Tutorial > Cancel invitation

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