Template Expression Expansion

[tfranklin]

Currently template expressions are limited to Name and Fullname for properties.  There's also no way to set template expressions programmatically.  I think it would be extremely beneficial to allow template expressions to reference any OPC property from an object relative to the template.  This would allow for dynamically configured fields such as control min/max, alarm conditions, tagname/itemid's, alarm sources, metadata, etc... 

Ex:  On a Analog in the template --> ControlMin = ".AI1.FullScale"
       AlarmSource = "..Name" + ' - ' + ".AI1.DisplayName"

In short, it enables a poor mans version of bindings for OPC properties.  Maybe what I'm more looking for is bindings in general for OPC properties.  Being able to set something like AlarmsDisabled = (".Flow Rate" = 0) quickly from a simple properties form rather than writing logic to do it every time would be pretty neat. 

[sbeadle]

Thank you. That would, however, make the instances need to be more 'aware' of field changes.

We had hoped that parameters would be used for this - set a full scale parameter which affects multiple fields.

[tfranklin]

Template Parameters are useful but we almost never use them because we haven't found a way to programmatically set them. I can see a use case for them for things like the alarm source mentioned above, but being limited to a right click->set template expression at the instance level just takes the incentive away. If there was a easy way to populate them I can see them being used much more widely. Then again, we punted on the idea of them a few years back so there may be a way to do so now.