<VB.NET>
Public Class
DBElement
Implements IExternalCommand
'' member
variables
Dim m_rvtApp As Application
Dim m_rvtDoc As Document
Public Function Execute(ByVal commandData
As ExternalCommandData, _
...
'' Get
the access to the top most objects.
Dim rvtUIApp As UIApplication =
commandData.Application
Dim rvtUIDoc As UIDocument =
rvtUIApp.ActiveUIDocument
m_rvtApp = rvtUIApp.Application
m_rvtDoc = rvtUIDoc.Document
'' ...
</VB.NET>