Get Parameter Unit in Revit 2021

[jmyr]

Hi guys,

How do i get the exact unit from specific parameter for example 

Calculated Heating Load = W

Calculated Heating Load per area = W/m²

and so on..

Parameter parameter = SELECTEDZone.get_Parameter(BuiltInParameter.ZONE_CALCULATED_COOLING_LOAD_PARAM);

ForgeTypeId units = parameter.GetUnitTypeId();

[jeremytammik · Accepted solution]

Please read the What's New description on the Forge type id and its use:

https://thebuildingcoder.typepad.com/blog/2020/04/whats-new-in-the-revit-2021-api.html#4.1.3

Maybe the discussion of Boost your BIM will help:

https://thebuildingcoder.typepad.com/blog/2020/07/virtual-au-and-aec-hackathon-units-and-das-job.htm...

[Charlie_Portelli_PHZAJ8NNHFJA]

Thanks for the info. It seems that as of Revit 2021 the below methods have been marked Obsolete.

• UnitUtils.GetSpecTypeId()
• UnitUtils.GetUnitType()
• UnitUtils.GetUnitTypeId()
• UnitUtils.GetDisplayUnitType()
• UnitUtils.GetSymbolTypeId()
• UnitUtils.GetUnitSymbolType()

If I have a Revit Parameter object that contains an area in square meters (25.4 sqM), can you help me identify how I could extract the number (25.4) and the unit type (sqM) from the Parameter? I'm aware I can use Parameter.AsValueString(), but this will give me the concatenated version. I'm trying to get the numbers and the units separately, and it's proving to be a bit tricky.

Thank you in advance.

[jeremy_tammik]

Dear Charlie,

Personally, for simple units such as length and area, I just implement the conversion myself, cf., e.g., The Building Coder samples:

https://github.com/jeremytammik/the_building_coder_samples

https://github.com/jeremytammik/the_building_coder_samples/blob/master/BuildingCoder/Util.cs#L1206-L...

[Charlie_Portelli_PHZAJ8NNHFJA]

Thanks @jeremy_tammik 

These are always helpful.

My current project requires me to travers all the parameters of various elements from different categories. I can easily get the parameter name, and value.

ParameterData paDa = new ParameterData();
paDa.ParameterName = param.Definition.Name;

switch (param.StorageType)
{
     case StorageType.String:
          paDa.ParameterValue = param.AsString(); break;
     case StorageType.Integer:
          paDa.ParameterValue = param.AsInteger().ToString(); break;
     case StorageType.Double:
          paDa.ParameterValue = param.AsDouble().ToString(); break;
     default:
          paDa.ParameterValue = param.AsValueString(); break;
}

My next goal is to get the unit type (mm, cm, cm2, ft, ft2, etc.). Since some of the parameters have complex unit types such as w/m2, I can't predict all the unit types to manually code them in. In order to get the UnitTypeID I'm using 

ForgeTypeId unitTypeId = param.GetUnitTypeId();

For my application it's important to have the parameter name, parameter value, and parameter unit type as separate fields, so that I may operate / query them individually. The obvious problem is that not every parameter has a Unit Type. So I have to run the line of code above in a try/catch block. Is there a way to identify if the parameter has a Unit Type before trying to execute the line of code above? I have a hunch the application is taking a performance hit since the try / catch block triggers quite often.

Thank you.