Echelon OpenLDV - Manual (Page 170)

162 Custom Lookup Extension Component Programming
Overview
This appendix describes the interfaces and methods that your custom lookup
extension component can use or must implement:
• Implement
o ILdvxConfigure (optional)
o ILdvxLookup (required)
• Use
o ILdvxSCO
o ILdvxSCO2
o ILdvxSCO_TCP
A lookup extension component must implement ILdvxLookup, and can
optionally implement ILdvxConfigure. During its operation, the lookup
extension component calls methods of the ILdvxSCO, ILdvxSCO2, and
ILdvxSCO_TCP interfaces. Types and error codes used by the RNIs are
declared in the LdvxTypes.h and LdvxResult.h header files, or in the Ldvx.tlb
type library.
The SampleLookupCsv.cpp and SampleLookupVBNet.vb sample lookup
extension components use the methods described in this chapter. See Sample
Lookup Extension Component on page 132 for more information about these
examples.
ILdvxConfigure Interface
This configuration interface is an optional interface implemented by an xDriver
lookup extension component. It defines methods that are used to pass
configuration information (instance name and options) to the lookup extension
component at instantiation.
SetInstance Method
Applies to: xDriver Lookup Extension Component
This method is passed the instance name of the lookup extension component for a
session. Typically, each profile has its own instance of a lookup extension
component.
Profiles can be configured to share an instance of an xDriver lookup extension
component by using the same instance name, which allows a single xDriver
lookup extension component to be shared by multiple profiles. The instance
name itself can be used as a key internally. You can set the lookup instance to be
used by a given xDriver profile with the OpenLDV xDriver Profile Editor. For
more information, see xDriver Profiles on page 134.