How to make the SAP Connector logout

Good morning,

I'm starting to use Sap connector with Visual Studio 2010 (vb.net) , everything works fine I get my information continues from a transaction Z , except that when I get the information I can not get to my Logout SAP

• as I make the logout of sap connector ?
• because when I use the sap connector in the transaction SM04 me two connections appear ?

I add my code to see how do the connections

Dim ofunc As IRfcFunction = oDestination.Repository.CreateFunction("ZFN_FACTUR_CLI_FECH")

ofunc.SetValue("variables", variables)

ofunc.SetValue("variables", variables)

ofunc.SetValue("variables", variables)

RfcSessionManager.BeginContext(oDestination)

ofunc.Invoke(oDestination)

ofunc.GetTable("table_variable")

RfcSessionManager.EndContext(oDestination)