Public Function BeginGetSingleLineAddressField( _
   ByVal callback As AsyncCallback, _
   ByVal asyncState As Object _
) As IAsyncResult

Dim instance As GeocodeServerProxy
Dim callback As AsyncCallback
Dim asyncState As Object
Dim value As IAsyncResult
 
value = instance.BeginGetSingleLineAddressField(callback, asyncState)

public IAsyncResult BeginGetSingleLineAddressField( 
   AsyncCallback callback,
   object asyncState
)