vb sip软电话

【实例简介】

只需要提供sipserverIP：

SIP账号

SIP密码

即可实现通信。所有配置请看实例截图

【实例截图】比较详细的sip软电话采用的是VAXvoipsdk

【核心代码】

Private Const SND_FILENAME = &H20000
Private Const SND_LOOP = &H8
Private Const SND_ASYNC = &H1
Private Const SND_NODEFAULT = &H2

Private Declare Function PlaySound Lib "winmm.dll" Alias "PlaySoundA" _
  (lpszName As Any, ByVal hModule As Long, ByVal dwFlags As Long) As Boolean

Private Sub BtnClearLog_Click()
    ListStatusLog.Clear
End Sub

Private Sub BtnDialPad0_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "0"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "0")
End Sub

Private Sub BtnDialPad1_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "1"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "1")
End Sub

Private Sub BtnDialPad2_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "2"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "2")
End Sub

Private Sub BtnDialPad3_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "3"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "3")
End Sub

Private Sub BtnDialPad4_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "4"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "4")
End Sub

Private Sub BtnDialPad5_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "5"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "5")
End Sub

Private Sub BtnDialPad6_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "6"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "6")
End Sub

Private Sub BtnDialPad7_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "7"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "7")
End Sub

Private Sub BtnDialPad8_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "8"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "8")
End Sub

Private Sub BtnDialPad9_Click()
    EditPhoneNo.Text = EditPhoneNo.Text "9"
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "9")
End Sub

Private Sub BtnDialPadStar_Click()
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "*")
End Sub

Private Sub BtnDialPadNo_Click()
    Result = VaxSIPUserAgentOCX.DigitDTMF(ListLines.ListIndex, "#")
End Sub

Private Sub BtnHelpMore_Click()
    HelpForm.Show vbModal
End Sub

Private Sub BtnPlayForward_Click()
    LineNo = ListLines.ListIndex
    Result = VaxSIPUserAgentOCX.PlayWaveSkipTo(LineNo, VaxSIPUserAgentOCX.PlayWavePosition(LineNo) 2)
    If Result = False Then
        ErrorMessages
    End If
End Sub

Private Sub BtnPlayPause_Click()
    LineNo = ListLines.ListIndex
    Result = VaxSIPUserAgentOCX.PlayWavePause(LineNo)
    If Result = False Then
        ErrorMessages
    End If
End Sub

Private Sub BtnPlayRewind_Click()
    LineNo = ListLines.ListIndex
    Result = VaxSIPUserAgentOCX.PlayWaveSkipTo(LineNo, VaxSIPUserAgentOCX.PlayWavePosition(LineNo) - 2)
    If Result = False Then
        ErrorMessages
    End If
End Sub

Private Sub BtnPlayStop_Click()
    LineNo = ListLines.ListIndex
    Result = VaxSIPUserAgentOCX.PlayWaveStop(LineNo)
    If Result = False Then
        ErrorMessages
    End If
End Sub

Private Sub BtnSetPlayFile_Click()
    LineNo = ListLines.ListIndex
    Result = VaxSIPUserAgentOCX.PlayWaveOpen(LineNo, EditPlayFileName.Text)
    If Result = False Then
        ErrorMessages
    End If
End Sub

Private Sub BtnStartPlay_Click()
    LineNo = ListLines.ListIndex
    Result = VaxSIPUserAgentOCX.PlayWaveStart(LineNo, CheckPlayListen.Value)
    If Result = False Then
        ErrorMessages
    End If
End Sub

Private Sub BtnTransferCall_Click()
    
    ToURI = "sip:" EditTransferPhoneNo.Text "@" EditSIPProxy.Text
    
    LineNo = ListLines.ListIndex
    
    Result = VaxSIPUserAgentOCX.TransferCall(LineNo, ToURI)
    If Result = False Then
        ErrorMessages
    End If
    
End Sub

Private Sub CheckAGC_Click()
    
    If CheckAGC.Value = 1 Then
        Result = VaxSIPUserAgentOCX.EnableAGC(8000)
        If Result = False Then
            ErrorMessages
        End If
    Else
        VaxSIPUserAgentOCX.DisableAGC
    End If
End Sub

Private Sub CheckMuteMic_Click()
    Result = VaxSIPUserAgentOCX.MuteMic(CheckMuteMic.Value)
End Sub

Private Sub CheckPlayRingTone_Click()
    
    If CheckPlayRingTone.Value <> 1 Then
      Retval = PlaySound(ByVal 0&, 0&, SND_ASYNC Or SND_FILENAME Or SND_LOOP Or SND_NODEFAULT)
    End If
    
End Sub

Private Sub CheckSpkMute_Click()
    Dim Result
    Result = VaxSIPUserAgentOCX.MuteSpk(CheckSpkMute.Value)
End Sub

Private Sub CheckStartConf_Click()
    
    BusyCount = 0
    
    For LineNo = 0 To 6
        If VaxSIPUserAgentOCX.IsLineBusy(LineNo) = True Then
            BusyCount = BusyCount 1
        End If
    Next LineNo
    
    If BusyCount < 2 And CheckStartConf.Value Then
        CheckStartConf.Value = False
        MsgBox ("Dial/receive more than one calls and then click start conference check box.")
    End If
    
End Sub

Private Sub CheckStartRecording_Click()

    If CheckStartRecording.Value = 1 Then
        Result = VaxSIPUserAgentOCX.StartRecording(ListLines.ListIndex, 2, True)
        If Result = False Then
            ErrorMessages
        End If
    Else
        Result = VaxSIPUserAgentOCX.StopRecording(ListLines.ListIndex)
    End If
    
End Sub

Private Sub Form_Unload(Cancel As Integer)
    Retval = PlaySound(ByVal 0&, 0&, SND_ASYNC Or SND_FILENAME Or SND_LOOP Or SND_NODEFAULT)
    
End Sub

Private Sub SliderMicVol_Click()
    ' SetMicVolume method requires Volume value from 0 to 255 range    '
    ' but the slider range is 0 to 10, so we multiply the slider value '
    ' to 25 to get the required value to pass to SetMicVolume method   '
    
    Dim Result
    Result = VaxSIPUserAgentOCX.SetMicVolume(SliderMicVol.Value * 25)
        
    If Result = False Then
        ErrorMessages
    End If
End Sub

Private Sub SliderSpkVol_Click()

' SetSpkVolume method requires Volume value from 0 to 255 range    '
' but the slider range is 0 to 10, so we multiply the slider value '
' to 25 to get the required value to pass to SetSpkVolume method   '
    
    Dim Result
    Result = VaxSIPUserAgentOCX.SetSpkVolume(SliderSpkVol.Value * 25)
    
    If Result = False Then
        ErrorMessages
    End If
    
End Sub

Private Sub ErrorMessages()

    Dim Error
    Error = VaxSIPUserAgentOCX.GetVaxObjectError
    
    If Error = 10 Then
        MsgBox ("You are not Online, please click the 'Online' button first.")
    End If
    
    If Error = 11 Then
        MsgBox ("Cann't open local communication port. Another softphone (x-Ten, x-lite or skype etc) is already running. Please close it first.")
    End If
    
    If Error = 12 Then
        MsgBox ("License Key is not valid.")
    End If
    
    If Error = 13 Then
        MsgBox ("Fail to initialize VaxVoIP task window.")
    End If
    
    If Error = 14 Then
        MsgBox ("Cann't access Input/Mic device or device is already in use.")
    End If
    
    If Error = 15 Then
        MsgBox ("Cann't access Output/Speaker device or device is already in use.")
    End If
    
    If Error = 16 Then
        MsgBox ("Input/Mic device is not open.")
    End If
    
    If Error = 17 Then
        MsgBox ("Output/Speaker device is not open.")
    End If
    
    If Error = 18 Then
        MsgBox ("Your sound device does not support mic volume.")
    End If
    
    If Error = 19 Then
        MsgBox ("Your sound device does not support speaker volume.")
    End If
    
    If Error = 20 Then
        MsgBox ("Recording media initialization fail.")
    End If
        
    If Error = 21 Then
        MsgBox ("Cann't open the wave file.")
    End If
    
    If Error = 22 Then
        MsgBox ("Provided SIP URI is not valid.")
    End If
    
    If Error = 23 Then
        MsgBox ("Codec is not supported.")
    End If
    
    If Error = 24 Then
        MsgBox ("Error to create SDP (Session Description Protocol) request.")
    End If
    
    If Error = 25 Then
        MsgBox ("Error to create CONNECTION request. Please check the provided SIP URI is valid.")
    End If
    
    If Error = 26 Then
        MsgBox ("Error to create REGISTER request. Please check the provided SIP URI is valid.")
    End If
    
    If Error = 27 Then
        MsgBox ("Error to create UN-REGISTER request. Please check the provided SIP URI is valid.")
    End If
    
    If Error = 28 Then
        MsgBox ("Error to create DISCONNECT request.")
    End If
            
    If Error = 29 Then
        MsgBox ("Line No is not valid.")
    End If
    
    If Error = 30 Then
        MsgBox ("Line is already busy.")
    End If
    
    If Error = 31 Then
        MsgBox ("Line is not open.")
    End If
    
    If Error = 32 Then
        MsgBox ("Invalid Call-Id.")
    End If
    
    If Error = 33 Then
        MsgBox ("Provided value is not valid.")
    End If
    
    If Error = 34 Then
        MsgBox ("Selected line is not in voice session.")
    End If
    
    If Error = 35 Then
        MsgBox ("Fail to read wave file.")
    End If
    
    If Error = 36 Then
        MsgBox ("Fail to write wave file.")
    End If
    
    If Error = 37 Then
        MsgBox ("Unsupported wave file format.")
    End If
        
End Sub

Private Function InitVaxVoIPObject(ByVal MyIP As String, ByVal FromURI As String) As Boolean

    Dim ListenPort As Integer
    Dim Result As Boolean
  
    Result = False
    ListenPort = 5060
        
    Do While ListenPort < 7000
    
        Result = VaxSIPUserAgentOCX.Initialize(False, MyIP, ListenPort, FromURI, EditOutBoundProxy.Text, EditSIPProxy.Text, EditLoginId.Text, EditLoginPwd.Text, True, 7)
        If Result = False Then
           
           If 11 <> VaxSIPUserAgentOCX.GetVaxObjectError() Then
               ErrorMessages
               Exit Do
           End If
           
        Else
           Exit Do
        End If
    
    ListenPort = ListenPort 1
    Loop
          
    If ListenPort >= 7000 Then
        MsgBox ("Cann't open SIP communication port.")
        Result = False
    End If
        
    InitVaxVoIPObject = Result
      
End Function

Private Function OpenLines(ByVal MyIP As String, ByVal TotalNoOfLine As Integer) As Boolean

    Dim ListenPort As Integer
    Dim Result As Boolean
    Dim ErrorCount As Integer
  
    Result = False
    ListenPort = 7000
    ErrorCount = 0
          
    For LineNo = 0 To (TotalNoOfLine - 1)
        
        Result = VaxSIPUserAgentOCX.OpenLine(LineNo, False, MyIP, ListenPort)
        If Result = False Then
           
           If 11 <> VaxSIPUserAgentOCX.GetVaxObjectError() Then
               ErrorMessages
               Exit For
           Else
               ErrorCount = ErrorCount 1
               LineNo = LineNo - 1
           End If
        
        End If
        
       ListenPort = ListenPort 2  ' It is importent to increament RTP Listen port by 2
        
       If ErrorCount >= (TotalNoOfLine 1000) Then  ' If unable to open more than 1000 ports.
            MsgBox ("Unable to open RTP communication port.")
            Result = False
            Exit For
       End If
        
    Next LineNo
                  
    OpenLines = Result
      
End Function
    
Private Sub BtnOnline_Click()
    
    Dim MyIP
    Dim FromURI
                
    If BtnOnline.Caption = "Offline" Then
       
       TimerTick.Enabled = False
       TimerProgressBar.Enabled = False
       
       SpkProgress.Value = 0
       MicProgress.Value = 0
              
       VaxSIPUserAgentOCX.UnInitialize
            
       ComboAudioIn.Clear
       ComboAudioOut.Clear
       
       BtnOnline.Caption = "Online"
                     
       Exit Sub
       
    End If
        
    If EditLoginId.Text = "" Then
        MsgBox ("Please enter the SIP proxy Login Id.")
        Exit Sub
    End If
    
    If EditSIPProxy.Text = "" Then
        MsgBox ("Please enter the SIP proxy address or URI.")
        Exit Sub
    End If
    
    VaxSIPUserAgentOCX.SetLicenceKey ("TRIAL-LICENSE-KEY")
            
    '****** Constructing SIP From URI for IP Telephony *******
    If EditDisplayName = "" Then
        FromURI = EditLoginId.Text " <sip:" EditLoginId.Text "@" EditSIPProxy.Text ">"
    Else
        FromURI = EditDisplayName.Text " <sip:" EditLoginId.Text "@" EditSIPProxy.Text ">"
    End If
    
    '********************************************************************
    '   Listen Port: default SIP port 5060.
    '     SIP Proxy: SIP Proxy IP or FQDN provided by your service provider.
    ' OutboundProxy: SIP outbound/NAT proxy IP or FQDN provided by your
    '                service provider to use SIP phone behind the NAT.
    '
    '*********************************************************************
    
    MyIP = VaxSIPUserAgentOCX.GetMyIP()
                    
    Result = InitVaxVoIPObject(MyIP, FromURI)
    If Result = False Then
        Exit Sub
    End If
    
    Result = OpenLines(MyIP, 7)
    If Result = False Then
        Exit Sub
    End If
          
    If CheckRegisterToProxy.Value = 1 Then
        Result = VaxSIPUserAgentOCX.RegisterToProxy(3600)
        If Result = False Then
            ErrorMessages
            Exit Sub
        End If
        
        AddToStatusLog ("Registering to SIP Proxy.")
    End If
        
    If CheckEchoCancel.Value Then
        VaxSIPUserAgentOCX.EnableEchoNoiseCancellation
    Else
        VaxSIPUserAgentOCX.DisableEchoNoiseCancellation
    End If
        
    VaxSIPUserAgentOCX.DeselectAllVoiceCodec
        
    If CheckGSM610.Value Then
        VaxSIPUserAgentOCX.SelectVoiceCodec (0)
    End If
        
    If CheckiLBC.Value Then
        VaxSIPUserAgentOCX.SelectVoiceCodec (1)
    End If
        
    If CheckG711A.Value Then
        VaxSIPUserAgentOCX.SelectVoiceCodec (2)
    End If
        
    If CheckG711U.Value Then
        VaxSIPUserAgentOCX.SelectVoiceCodec (3)
    End If

    VaxSIPUserAgentOCX.EnableKeepAlive (10)
        
    BtnOnline.Caption = "Offline"
        
    UpdateSoundDevices
               
    TimerTick.Enabled = True
    TimerProgressBar.Enabled = True
               
                    
End Sub

Private Sub VaxSIPUserAgentOCX_OnCallTransferAccepted(ByVal LineNo As Long)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Transfer accepted.")
End Sub

Private Sub VaxSIPUserAgentOCX_OnConnecting(ByVal LineNo As Long)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Connecting.")
End Sub

Private Sub VaxSIPUserAgentOCX_OnDisconnectCall(ByVal LineNo As Long)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Hung up.")
End Sub

Private Sub VaxSIPUserAgentOCX_OnDTMFDigit(ByVal LineNo As Long, ByVal Digit As String)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Key-pressed: " Digit)
End Sub

Private Sub VaxSIPUserAgentOCX_OnFailToConnect(ByVal LineNo As Long)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Fail to connect.")
End Sub

Private Sub VaxSIPUserAgentOCX_OnFailToRegister()
    AddToStatusLog ("Fail to register.")
End Sub

Private Function FindCallIdFromList(ByVal CallId As String) As Boolean
    
    Dim Result As Boolean
    
    Result = False
    
    For ListIndex = 0 To (ListIncomingCallIds.ListCount - 1)
       
        If UCase(ListIncomingCallIds.List(ListIndex)) = UCase(CallId) Then
          Result = True
          Exit For
        End If
    
    Next ListIndex
    
    FindCallIdFromList = Result
    
End Function

Private Sub VaxSIPUserAgentOCX_OnGeneralFailureResponse(ByVal LineNo As Long, ByVal StatusCode As Long, ByVal ReasonPhrase As String)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) " Response: " ReasonPhrase)
End Sub

Private Sub VaxSIPUserAgentOCX_OnIncomingCall(ByVal CallId As String, ByVal DisplayName As String, ByVal UserName As String, ByVal FromURI As String, ByVal ToURI As String)
    
    If FindCallIdFromList(CallId) = False Then
        ListIncomingCallIds.AddItem (CallId)
        
        If Len(DisplayName) <> 0 Then
           ListIncomingCall.AddItem ("CLI: " DisplayName)
        Else
           ListIncomingCall.AddItem ("CLI: " UserName)
        End If
        
    End If
    
    If ListIncomingCall.ListIndex = -1 And ListIncomingCall.ListCount > 0 Then
        ListIncomingCall.ListIndex = 0
    End If
    
End Sub

Private Sub VaxSIPUserAgentOCX_OnIncomingCallRingingStart(ByVal CallId As String)
    
    If CheckPlayRingTone.Value = 1 Then
        Retval = PlaySound(ByVal "ring.wav", 0&, SND_ASYNC Or SND_FILENAME Or SND_LOOP Or SND_NODEFAULT)
    End If
        
End Sub

Private Sub VaxSIPUserAgentOCX_OnIncomingCallRingingStop(ByVal CallId As String)
    RemoveCallIdFromList (CallId)
    Retval = PlaySound(ByVal 0&, 0&, SND_ASYNC Or SND_FILENAME Or SND_LOOP Or SND_NODEFAULT)
End Sub

Private Sub VaxSIPUserAgentOCX_OnPlayWaveDone(ByVal LineNo As Long)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Play wave done.")
End Sub

Private Sub VaxSIPUserAgentOCX_OnProvisionalResponse(ByVal LineNo As Long, ByVal StatusCode As Long, ByVal ReasonPhrase As String)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Response: " ReasonPhrase)
End Sub

Private Sub VaxSIPUserAgentOCX_OnRedirectionResponse(ByVal LineNo As Long, ByVal StatusCode As Long, ByVal ReasonPhrase As String, ByVal Contact As String)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Response: " ReasonPhrase)
End Sub

Private Sub VaxSIPUserAgentOCX_OnRequestFailureResponse(ByVal LineNo As Long, ByVal StatusCode As Long, ByVal ReasonPhrase As String)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Response: " ReasonPhrase)
End Sub

Private Sub VaxSIPUserAgentOCX_OnServerFailureResponse(ByVal LineNo As Long, ByVal StatusCode As Long, ByVal ReasonPhrase As String)
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Response: " ReasonPhrase)
End Sub

Private Sub VaxSIPUserAgentOCX_OnSuccessToConnect(ByVal LineNo As Long, ByVal ToRTPIP As String, ByVal ToRTPPort As Long)
    
    If LineNo <> ListLines.ListIndex Then
        VaxSIPUserAgentOCX.HoldLine (LineNo)
        ListLines.List(LineNo) = "Line-" Trim(Str(LineNo 1)) " : HOLD"
    Else
        ListLines.List(LineNo) = "Line-" Trim(Str(LineNo 1)) " : BUSY"
    End If
    
    AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Success to connect.")
    
    Result = VaxSIPUserAgentOCX.GetSpkVolume()
    SliderSpkVol.Value = Result / 25
    
    Result = VaxSIPUserAgentOCX.GetMicVolume()
    SliderMicVol.Value = Result / 25
     
    Result = VaxSIPUserAgentOCX.IsMicBoostEnable()
    If Result = True Then
      CheckMicBoost.Value = 1
    Else
      CheckMicBoost.Value = 0
    End If
    
End Sub

Private Sub VaxSIPUserAgentOCX_OnSuccessToRegister()
    AddToStatusLog ("Registered successfully.")
End Sub

Private Sub VaxSIPUserAgentOCX_OnTryingToRegister()
    AddToStatusLog ("Trying to register.")
End Sub

Private Sub VaxSIPUserAgentOCX_OnTryingToUnRegister()
    AddToStatusLog ("Trying to Unregister.")
End Sub

Private Sub VaxSIPUserAgentOCX_OnSuccessToUnRegister()
    AddToStatusLog ("Unregistered successfully.")
End Sub

Private Sub VaxSIPUserAgentOCX_OnFailToUnRegister()
    AddToStatusLog ("Fail to unregister.")
End Sub

Private Sub BtnDial_Click()
    
    Dim ToURI
    Dim Result
       
    If EditPhoneNo.Text = "" Then
        MsgBox ("Please enter a phone number.")
        Exit Sub
    End If
    
    '*******************************************************
    '       Constructing SIP To URI for IP Telephony:
    '                sip:PhoneNumber@SIP Proxy
    '********************************************************
    
    ToURI = "sip:" EditPhoneNo.Text "@" EditSIPProxy.Text
            
    LineNo = FindLine()
    If LineNo = -1 Then
        MsgBox ("No line is free")
        Exit Sub
    End If
            
    Result = VaxSIPUserAgentOCX.Connect(LineNo, ToURI, ComboAudioIn.ListIndex - 1, ComboAudioOut.ListIndex - 1)
    If Result = False Then
        ErrorMessages
    Else
        AddToStatusLog ("Line-" Trim(Str(LineNo 1)) ": Dialing.")
        
        ListLines.List(LineNo) = "Line-" Trim(Str(LineNo 1)) " : CONNECTING"
        
    End If
    
End Sub

Private Sub BtnHangUp_Click()
    
    Dim Result
    LineNo = ListLines.ListIndex
    
    Result = VaxSIPUserAgentOCX.Disconnect(LineNo)
    If Result = False Then
        ErrorMessages
    End If
            
End Sub

Private Sub RemoveCallIdFromList(ByVal CallId As String)
    
    For ListIndex = 0 To (ListIncomingCallIds.ListCount - 1)
       
        If UCase(ListIncomingCallIds.List(ListIndex)) = UCase(CallId) Then
          ListIncomingCall.RemoveItem (ListIndex)
          ListIncomingCallIds.RemoveItem (ListIndex)
          ListIndex = ListIndex - 1
        End If
    
    Next ListIndex
    
End Sub

Private Sub BtnAccept_Click()
    
    SelectedItemIndex = ListIncomingCall.ListIndex
    If SelectedItemIndex = -1 Then
        Exit Sub
    End If
                        
    LineNo = FindLine()
    If LineNo = -1 Then
        MsgBox ("No line is free")
        Exit Sub
    End If
    
    CallId = ListIncomingCallIds.List(SelectedItemIndex)
    Result = VaxSIPUserAgentOCX.AcceptCall(LineNo, CallId, ComboAudioIn.ListIndex - 1, ComboAudioOut.ListIndex - 1)
    If Result = False Then
        ErrorMessages
        Exit Sub
    End If
        
    Retval = PlaySound(ByVal 0&, 0&, SND_ASYNC Or SND_FILENAME Or SND_LOOP Or SND_NODEFAULT)
    
    RemoveCallIdFromList (CallId)
        
    If ListIncomingCall.ListIndex = -1 And ListIncomingCall.ListCount > 0 Then
        ListIncomingCall.ListIndex = 0
    End If
    
    ListLines.List(LineNo) = "Line-" Trim(Str(LineNo 1)) " : CONNECTING"
    
End Sub

Private Sub BtnReject_Click()
    
    SelectedItemIndex = ListIncomingCall.ListIndex
    If SelectedItemIndex = -1 Then
        Exit Sub
    End If
                        
    CallId = ListIncomingCallIds.List(SelectedItemIndex)
    Result = VaxSIPUserAgentOCX.RejectCall(CallId)
    If Result = False Then
        ErrorMessages
        Exit Sub
    End If
    
    Retval = PlaySound(ByVal 0&, 0&, SND_ASYNC Or SND_FILENAME Or SND_LOOP Or SND_NODEFAULT)
        
    RemoveCallIdFromList (CallId)
        
    If ListIncomingCall.ListIndex = -1 And ListIncomingCall.ListCount > 0 Then
        ListIncomingCall.ListIndex = 0
    End If
       
End Sub

Private Sub BtnResetRecordingBuffer_Click()
    
    LineNo = ListLines.ListIndex
    VaxSIPUserAgentOCX.ResetRecording (LineNo)
    
End Sub

Private Sub BtnSaveToWaveFile_Click()
    Dim Result
    
    LineNo = ListLines.ListIndex
    Result = VaxSIPUserAgentOCX.SaveRecordingToWaveFile(LineNo, EditSaveFileName.Text)
    If Result = False Then
        ErrorMessages
        Exit Sub
    End If
   
    MsgBox ("Saved Successfully")
End Sub

Private Sub ChkStartRecording_Click()
        
    Dim Result
        
    LineNo = ListLines.ListIndex
    
    If ChkStartRecording.Value = 1 Then
        Result = VaxSIPUserAgentOCX.StartRecording(LineNo, 2)
    Else
        Result = VaxSIPUserAgentOCX.StopRecording(LineNo)
    End If
End Sub

Private Sub CheckEchoCancel_Click()
    If CheckEchoCancel.Value = 1 Then
        VaxSIPUserAgentOCX.EnableEchoNoiseCancellation
    Else
        VaxSIPUserAgentOCX.DisableEchoNoiseCancellation
    End If
End Sub

Private Sub CheckMicBoost_Click()
    If CheckMicBoost.Value = 1 Then
        VaxSIPUserAgentOCX.EnableMicBoost
    Else
        VaxSIPUserAgentOCX.DisableMicBoost
    End If
End Sub

Private Sub CheckDisturb_Click()
    If CheckDisturb.Value = 1 Then
        VaxSIPUserAgentOCX.EnableDonotDisturb
    Else
        VaxSIPUserAgentOCX.DisableDonotDisturb
    End If
End Sub

Private Sub CheckGSM610_Click()
    
    '****Codec No 0 represents GSM 6.10 *****
    
    If CheckGSM610.Value = 1 Then
        VaxSIPUserAgentOCX.SelectVoiceCodec (0)
    Else
        VaxSIPUserAgentOCX.DeselectVoiceCodec (0)
    End If
End Sub

Private Sub CheckiLBC_Click()
    
    '****Codec No 1 represents iLBC *****
    
    If CheckiLBC.Value = 1 Then
        VaxSIPUserAgentOCX.SelectVoiceCodec (1)
    Else
        VaxSIPUserAgentOCX.DeselectVoiceCodec (1)
    End If
End Sub

Private Sub CheckG711A_Click()
    
    '****Codec No 2 represents G711 A-LAW *****
    
    If CheckG711A.Value = 1 Then
        VaxSIPUserAgentOCX.SelectVoiceCodec (2)
    Else
        VaxSIPUserAgentOCX.DeselectVoiceCodec (2)
    End If
End Sub

Private Sub CheckG711U_Click()
    
    '****Codec No 3 represents G711 U-LAW *****
    
    If CheckG711U.Value = 1 Then
        VaxSIPUserAgentOCX.SelectVoiceCodec (3)
    Else
        VaxSIPUserAgentOCX.DeselectVoiceCodec (3)
    End If
End Sub

Private Sub UpdateSoundDevices()
        
    ComboAudioIn.Clear
    ComboAudioIn.AddItem ("Default Device")
    
    For DeviceId = 0 To VaxSIPUserAgentOCX.GetAudioInDevTotal() - 1
        ComboAudioIn.AddItem (VaxSIPUserAgentOCX.GetAudioInDevName(DeviceId))
    Next DeviceId
    
    ComboAudioIn.ListIndex = 0
    
    ComboAudioOut.Clear
    ComboAudioOut.AddItem ("Default Device")
    
    For DeviceId = 0 To VaxSIPUserAgentOCX.GetAudioOutDevTotal() - 1
        ComboAudioOut.AddItem (VaxSIPUserAgentOCX.GetAudioOutDevName(DeviceId))
    Next DeviceId
    
    ComboAudioOut.ListIndex = 0
    
End Sub

Private Function FindLine() As Integer
    
    LineNo = ListLines.ListIndex
    
    If VaxSIPUserAgentOCX.IsLineBusy(LineNo) = False Then
        FindLine = LineNo
        Exit Function
    End If
       
    For LineNo = 0 To 6
        
        If VaxSIPUserAgentOCX.IsLineBusy(LineNo) = False Then
            FindLine = LineNo
            Exit Function
        End If
        
    Next LineNo
    
    FindLine = -1
    
End Function

Private Sub TimerProgressBar_Timer()
    
    SpkProgress.Value = VaxSIPUserAgentOCX.GetSpkSoundLevel()
    MicProgress.Value = VaxSIPUserAgentOCX.GetMicSoundLevel()
    
End Sub

Private Sub AddToStatusLog(ByVal StatusLog As String)
        ListStatusLog.AddItem (StatusLog)
        ListStatusLog.TopIndex = ListStatusLog.ListCount - 1
End Sub

Private Sub UpdateListLine(LineNo As Integer)

    If CheckStartConf.Value Then
        For LineCount = 0 To 6
            If VaxSIPUserAgentOCX.IsLineHold(LineCount) Then
                VaxSIPUserAgentOCX.UnHoldLine (LineCount)
            End If
        Next LineCount
    Else
        
        For LineCount = 0 To 6
            If LineCount <> LineNo Then
                If ((VaxSIPUserAgentOCX.IsLineBusy(LineCount) = True) And (VaxSIPUserAgentOCX.IsLineHold(LineCount) = False)) Then
                    VaxSIPUserAgentOCX.HoldLine (LineCount)
                End If
            End If
        Next LineCount
        
        If VaxSIPUserAgentOCX.IsLineHold(LineNo) Then
            VaxSIPUserAgentOCX.UnHoldLine (LineNo)
        End If
        
    End If

End Sub

Private Sub TimerTick_Timer()
    
    If ListLines.ListCount = 0 Then
        For LineNo = 0 To 6
            ListLines.AddItem ("Line-" Trim(Str(LineNo 1)) " : FREE")
        Next LineNo
        
        ListLines.ListIndex = 0
    End If
    
    UpdateListLine (ListLines.ListIndex)
    
    If (VaxSIPUserAgentOCX.IsRecording(ListLines.ListIndex) = True) <> (CheckStartRecording.Value = 1) Then
        If VaxSIPUserAgentOCX.IsRecording(ListLines.ListIndex) Then
            CheckStartRecording.Value = 1
        Else
            CheckStartRecording.Value = 0
        End If
    End If
            
    For LineNo = 0 To 6
            
        ItemText = ListLines.List(LineNo)
                                
        If VaxSIPUserAgentOCX.IsLineOpen(LineNo) = False Then
              
            If InStr(ItemText, "CLOSE") = 0 Then
                ListLines.List(LineNo) = "Line-" Trim(Str(LineNo 1)) " : CLOSE"
            End If
        
        Else
            If VaxSIPUserAgentOCX.IsLineBusy(LineNo) = True Then
                
                If VaxSIPUserAgentOCX.IsWaveFilePlaying(LineNo) = True Then
                    If InStr(ItemText, "PLAYING") = 0 Then
                        ListLines.List(LineNo) = "Line-" Trim(Str(LineNo 1)) " : PLAYING"
                    End If
                Else
                    If VaxSIPUserAgentOCX.IsLineHold(LineNo) = True Then
                        If InStr(ItemText, "HOLD") = 0 Then
                            ListLines.List(LineNo) = "Line-" Trim(Str(LineNo 1)) " : HOLD"
                        End If
                    Else
                        If (InStr(ItemText, "BUSY") = 0) And (InStr(ItemText, "CONNECTING") = 0) Then
                            ListLines.List(LineNo) = "Line-" Trim(Str(LineNo 1)) " : BUSY"
                        End If
                    End If
                End If
            Else
                If InStr(ItemText, "FREE") = 0 Then
                    ListLines.List(LineNo) = "Line-" Trim(Str(LineNo 1)) " : FREE"
                End If
            End If
        
        End If
                    
    Next LineNo

End Sub