Application: SpanDirection
Revit product and version: Revit Structure 2008
Last Modified: 19/12/2006
Modified By: JJ Autodesk HSL
Programming Language: C#

Subject:  This sample demonstrates how to get span direction and span direction symbols of structural Floor (Slab).

Classes: 
Autodesk.Revit.IExternalCommand
Autodesk.Revit.ElementSet
Autodesk.Revit.Elements.Floor
Autodesk.Revit.ElementArray
Autodesk.Revit.ElementArrayIterator

Project Files: 
Command.cs
This file contains the class Command which inherits from IExternalCommand interface and implements the Execute method, the class implements all functionalities of getting relevant information of Floor.

Description: 
This sample uses Floor class mostly to implement the functionality of getting properties of Floor (Slab): span direction angle and span direction symbols.
-	Floor objects can be gotten from ActiveDocument.Selection.Elements.
-	Floor.SpanDirectionAngle and Floor.SpanDirectionSymbols properties can be used to retrieve the span direction angle and span direction symbols of Floor (Slab).
-	To get span direction symbols, Element.ObjectType.Name 

Instructions: 
1.	Start Revit Structure, draw one slab in Reivt, and then select it.
2.	Click the external command, a message box will pop up, the span direction angle and span direction symbols of this slab will be shown afterwards. 
3.	If you fail to create a slab with span direction, please use “Structural Analysis-Default.rte” file as Revit Structure default template file.