Creating an empty tree

Replies to This Discussion

Permalink Reply by Vicente Soler on August 8, 2012 at 2:16pm

I'm not sure if this is the best way but this seems to generate a datatree with branches but nothing inside of them:

    Dim dt As New datatree(Of Object)
    For i As Integer = 0 To 9
      dt.addrange(New list(Of Object), New gh_path(i))
    Next
    a = dt

Permalink Reply by Andy VanMater on August 9, 2012 at 3:33pm

you can create empty branches in loops also. In reality once you do the line

Dim dt As New DataTree(Of Object)

you have created an empty datatree. If it needs branches then you need to add something to it. For an if/then statement if you want the thing to add an empty branch you can write the word "nothing" and it will do that. The following script can create a totally empty datatree.

For i As int32 = 0 To 5
For j As int32 = 0 To 20
dt.add(Nothing, New GH_Path(i))
Next
Next

a = dt

Permalink Reply by Dave Johnson on August 9, 2012 at 5:43pm

Yes, I needed an empty tree with some branch structure.

I'm writing in C#, not VB, but isn't this in C#:

Add(null, somePath); 

equivalent to adding "Nothing" in VB? If so, then it still adds something...a null, and calling ClearData() is still needed to make the tree empty.

Permalink Reply by Vicente Soler on August 9, 2012 at 6:29pm

Try my method, it doesn't create null items.

Permalink Reply by David Rutten on August 10, 2012 at 6:42am

You can also use the DataTree<T>.EnsurePath method. Which will add an empty branch if the path doesn't yet exist.

--

David Rutten

david@mcneel.com

Poprad, Slovakia