Using NBehave bdd library ActionSteps attribute you can expose to outside class which contains methods defined as Given,When or Then action steps:
BddSpecAssist (BSA) provides syntax highlighting for spec (Given,When,Then,Parameter tokens) and intellisense through action steps. Intellisence model keeps itsself up to date by observing following file events: change, add, delete.
BSA bound already typed parameter values for suggestions. In the screen below 'order1' parameter value was bound for all suggestions.
BSA allows to navigate to step definition by setting cursor on step in spec and pressing Shift + Tab.