[RESOLVED] invocation exception using AutoResetEvent

[steve_rm]

Hello,

I am using a background worker to process some login information. However, the background worker has to stop and wait for 2 events to happen. Once these have finished the background worker can complete its job. They are callback that will call the Set() method of the AutoResetEvent.

So I am using AutoResetEvent to set when these 2 events have finished. However, I seemed to be getting this error message

"Exception has been thrown by the target of an invocation."

and Inner exception

"Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index".

The exception usually fires when the registration success leaves scope.

Many thanks for any advice

The code for the background worker.

' Waiting for 'Account in use' and 'Register success or failure'
Private loginWaitEvents() As AutoResetEvent = { New AutoResetEvent(False), New AutoResetEvent(False) }

Private Sub bgwProcessLogin_DoWork(ByVal sender As Object, ByVal e As DoWorkEventArgs)
		  Console.WriteLine("Wait until event is set or timeout")
		  loginWaitEvents(0).WaitOne(3000, True)

		  If Me.accountInUseFlag Then
					If Me.lblRegistering.InvokeRequired Then
						Me.lblRegistering.Invoke(New UpdateRegisterLabelDelegate(Me.UpdateRegisterLabel), "Account in use")
					Else
						Me.lblRegistering.Text = "Account in use"
					End If
					' Failed attemp
					e.Cancel = True
					' Reset flag
					Me.accountInUseFlag = False
					Return
		   Else
					' Report current progress
					Me.bgwProcessLogin.ReportProgress(7, "Account accepted")
		   End If

			Console.WriteLine("Just Wait the result of successfull login or not")
			loginWaitEvents(1).WaitOne()

			If Me.registerSuccess Then
					' Report current progress
					Me.bgwProcessLogin.ReportProgress(7, "Register Succesfull")
					' Reset flag
					Me.registerSuccess = False
			Else
					If Me.lblRegistering.InvokeRequired Then
						Me.lblRegistering.Invoke(New UpdateRegisterLabelDelegate(Me.UpdateRegisterLabel), "Failed to register")
					Else
						Me.lblRegistering.Text = "Failed to register"
					End If
					' Failed attemp
					e.Cancel = True
					Return
			End If
End Sub

' Wait for the callback to set the AutoResetEvent

' Error sometimes happens when the function leaves scope.
Private Sub VaxSIPUserAgentOCX_OnSuccessToRegister(ByVal sender As Object, ByVal e As EventArgs)
			Console.WriteLine("OnSuccessToRegister() [ Registered successfully ]")
			Me.registerSuccess = True
			Me.loginWaitEvents(1).Set()
End Sub


' If the flag is not set, then just time out after 3 seconds for the first LoginWaitEvent.waitOne(3000, true)
 Private Sub VaxSIPUserAgentOCX_OnIncomingDiagnostic(ByVal sender As Object, ByVal e As AxVAXSIPUSERAGENTOCXLib._DVaxSIPUserAgentOCXEvents_OnIncomingDiagnosticEvent)
			Dim messageSip As String = e.msgSIP

			'Indicates that a user is already logged on (Accout in use).
			Dim sipErrorCode As String = "600 User Found"
			If messageSip.Contains(sipErrorCode) Then
				' Set flag for account in use
				Me.accountInUseFlag = True
				Console.WriteLine("OnIncomingDiagnostic() WaitEvent.Set() accountInUseFlag: " & Me.accountInUseFlag)
				loginWaitEvents(0).Set()
			End If
 End Sub