Revit – Setting Parameters Values in Macro Programming (with VB.Net)

Back in the old days, it was easy to set any parameter value in macro. This was the code I was using in Revit 2014:


element.parameter("Any Parameter Name").set("value")

This was working for Build-in Parameters, Sheared Parameters and Project Parameters. When I migrated some macros to Revit 2017 this formula wasn’t working any more. After some search I found a solution. Unfortunately for every parameter type it’s different.

Build-in Parameters:

Build-in Parameters can be set by referencing to parameter Definition name.

in VB.Net


in Python for Windows Comments parameter:


Parameter Definition Name one can find using Revit Lookup or in API help.

Example in VB.Net from my amended macro for sheet parameters: Drawn By, Checked By and Sheet Issue Date:


Shared Parameters:

Shared Parameters can be set by referencing their GUID number.

in VB.Net:

element.parameter(New Guid("guid-wierd-number").[set]("value")

in Python in Dynamo it DOESN’T WORK:

from System import Guid

NewGuid = Guid("7839a188-7b93-457a-9c33-0a4940183f18")

Guid Number for Shared Parameters can be found in Shared Parameter file i.e

Code example in VB.Net from my amended macro:

 m_vs.parameter(New Guid("3c5aa4ef-99ff-4a51-abfe-7f7129b9fed4")).[Set](curSheet.documentType)

Project Parameters:

Project Parameters can be set by referencing in the formula parameter’s Definition by itself.

in VB.Net:

 Dim ParameterList As IList(Of Parameter)
 Parameterlist = element.GetParameters("Parameter Name")
 Dim Parameter As Parameter
 Parameter = ParameterList(0)

in Python in Dynamo it DOESN’T WORK:

ParameterList = element.GetParameters("Parameter Name")
Parameter = ParameterList[0]

Is unsubscriptable  with get_Parameter or expects BuiltInParamter.

Any one knows how to make it work in Python in Dynamo?


2 thoughts on “Revit – Setting Parameters Values in Macro Programming (with VB.Net)”

  1. Hi and thanks for the thread. I am a complete newbie at this but I have dived in and created a VB.NET macro that I need to add data from an excel spreadsheet to create sheets from a list and also populate project parameter fields. Such as “S+D_Sheet Category” which is a string etc.
    If I have the following:

    m_vs = ViewSheet.Create(curDoc, tblock.Id)
    m_vs.parameter(“S+D_Sheet Category”).[Set](curSheet.sortCategory)

    This doesn’t work and says “Conversion from string “S+D_Sheet Category” to type ‘integer’ is not valid.

    How do I assign values within a List to project parameters?
    I can share the complete code if necessary.

    Thanks in advance!

    1. Hi,
      I’m sorry but I wasn’t checking this site for months.

      I suppose you are referring to a Project Parameter which is sorting your sheets so you should use this formula:
       Dim ParameterList As IList(Of Parameter)
       Parameterlist = element.GetParameters(“Parameter Name”)
       Dim Parameter As Parameter
       Parameter = ParameterList(0)
      You need to point to a Parameter.Definition and this is not a sting.
      “Parameter Name” replace with “S+D_Sheet Category”.

      if this wont work I would suggest to use ArchSmarter Sheet and View Maker. I converted it to work with Revit 2017 long time ago and I added a Project Parameter to it.
      I can share it if you steel need it.


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