Using Dynamo to Generate Mark Parameters from Information in Families

I recently had a question as a follow up to my bi-direction Excel using Dynamo post

Hi Ryan,

I’m trying to use the same concepts to export all structural columns. The node you used (family types) only exports 1 type at the time.

Do you know if there’s a node that lets me export all types of the column family I use in the project?

The node that you want to use to do this is All Elements of Category which you need to feed with your selection from the Categories node.

I thought I would share an example of how I used this node to generate individual type marks for all the columns on the project based off the family name and the level that the column is located on.

Of course generating the mark parameter from the family name means that you need a fairly solid and consistent naming convention in place. You could also use other type parameters within the family, this is just the method that I chose as an example.

Before we get started, I have used the Revit 2015 Sample Structure Project.RVT file and renamed the family types like so


The overview of this particular example of the Dynamo Script looks something like this, so let’s step through what it is doing.


Getting started, we use our Categories node which we use to select our Structural Columns category. As mentioned earlier we feed that into the All Elements of Category node.


Stepping through the top row, our elements feed into the Element.GetParameterValueByName node, and we’re picking up the Base Level parameter.



We then pass through to the Level.Name parameter which gives us the level name as you see it in the project browser as a string, which in this case is “01 – Entry Level”. Using the String.Split node we split the string in half using a Code Block node and entering ” “; into the code block to denote the space.

Think of this as the same as the Text to Columns command in Excel.

This gives us a list that splits the level name into

“01” “-” “Entry” “Level”

From here, run the data through the List.Transpose node and then finally into the List.GetItemAtIndex node, here we need the row at line 0 so we use a Number node to define the index.

You can alternatively use a Code Block node and enter “0”; as the code which works the same as the Number node.

On the bottom row we are taking our family type name and pulling out the type itself from the string that is returned. Even though when scheduling the Type parameter returns just the type, the string that is actually returned from Dynamo is in the format of Family Type: CRC 450, Family Name: STR_CONCRETE_ROUND_COLUMN.

So following a similar sequence to the top row, we split the string down to what we want which is “CRC 450”, to do this we need to split the string twice; first by the colon ( : ) and then by the comma ( , ). As you can see in the screenshot we need to transpose the list and pull the data at each row twice to get what we’re after.


At the lower right corner there is a number generator. It is simply stepping from 1 to 200 in increments of one. Make sure to run the Number.Sequence node through the List.Transpose otherwise you will cause Dynamo to lock up while generating incredibly long number strings if you feed the sequence directly into the mark parameter.


Finally, we use a Code.Block node to concatenate the data we have pulled into a single string. The code block is simply a+b+c+d; which gives as four variables of the same name that we can feed the rest of our data into.

I have then created another list which consists of the Element ID and the string, we then finish up by selecting our string and populating the mark parameter as per my bi-directional Excel post.

Of course there are other options where you can generate the mark parameter from other type parameters in the family, I just chose to use the type name as the example this time around as I could show how you could break down a long string and the data you need from it.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.