Parameters
- linkdata
- if the model is an Northwoods.GoXam.Model.ILinksModel, this is the link data; otherwise this is a PartManager.VirtualLinkData
- model
Return Value
If there is no category associated with the link data,
this uses the category of the "from" node data if it is not an empty string,
or else tries to use the category of the "to" node data.
The default category is the empty string.