5 Replies Latest reply on Feb 20, 2018 3:33 AM by Ronny Engmann

    How to check if block instance is nested?

    Ronny Engmann



      attached you'll find an example drawing incl. two blocks and a macro. That macro gets the coordinates of the instances of the selected block.


      Select Block1 in the FM and run the macro. The coordinates of the block instances will be shown in the immediate window.


      As you can see these coordinates are correct as long as the block instance does not belong to a nested block. If it is nested it will obviously give the position within the parental block (as "Block1-2" is definitely not located at x=0/y=0).


      Now my question is how can I check if a block instance is nested and what are the higher level block instances. If I knew that I could calculate the correct position adding the coordinates of the parental block(s).


      Any idea?


      Thanks in advance.


      Kind regards,



      PS: This is a simplified drawing. I know that the block position also depends on the sheet scale and, if placed in a view, on the view scale. I did not consider that in my example drawing to keep it simple and focussed on my question.

        • Re: How to check if block instance is nested?
          Josh Brady

          I will try to take a look at this in a bit, but I wanted to commend you on an excellent question!  This is one of the best-asked, most complete, and concise posts I've ever seen on this forum.  Kudos!

            • Re: How to check if block instance is nested?
              Ronny Engmann

              Hi Josh,


              thank you.


              To be honest my post still was not complete: I forgot to mention that I've also created an SR for that and it lead into an SPR (1067857: API: how to check if block instance is nested). The SR is still open and I hoped to find some other ideas here because I know there a lot of very intelligent and helpful people posting here.


              Kind regards,



                • Re: How to check if block instance is nested?
                  Josh Brady

                  So I played with this a little bit...


                  A solution to your problem may run a little deeper.  Sorry, I'm on 2017 so I couldn't use your file, but what I found was that nested block instances only exist once, no matter how many instances of the parent exist.


                  What I mean is, that if you insert Block A, then nest it inside Block B, you can make as many as you want of Block B and there is still only one instance of Block A.  Of course, you can still make more independent instances of A, but only one instance of A will exist for all nested ones. 


                  So the question is... How are you looking to use this information?  Do you want the user to select something? Or iterate through things?


                  If you want to get the coordinates of every Block A, including ones that don't really "exist" because they're part of Block B, I think you may have to:


                  Inside your current Instances loop:

                       Get TheInstance

                       Get coordinates of TheInstance

                       Get all block definitions from SketchManager

                       For each TheDefinition

                            Get definition sketch

                            Get all block instances inside that sketch

                            Check if any block instance IS TheInstance

                            Get all SubInstance of TheDefinition

                            For each SubInstance

                                 Modify SubInstance coordinates with TheInstance coords


                  I guess the above will have to be sort of iterative because Block B could be nested inside Block C, and so on to any number of levels.

                    • Re: How to check if block instance is nested?
                      Josh Brady

                      Here, give this a look.  Sorry, it's pretty bodgy.  I re-used a couple of variables you were done with 'cuz I'm lazy.


                      This doesn't do everything in the pseudocode loop, but it does do what you requested in your original post....


                      It's sorta like reachin' one arm shoulder deep into a noodlin' hole, grabbin' holt to a tail, then reachin' the other arm in the next hole, grabbin' some whiskers, and then figgerin' out if ya got holt to the same dang mud cat.


                      ' Precondition:
                      '          (1) Drawing is open that contains at least
                      '              one block definition with at least one
                      '              block instance.
                      '          (2) The block definition is selected in the
                      '              FeatureManager design tree.
                      ' Postconditions: None
                      Option Explicit
                      Dim swApp As SldWorks.SldWorks
                      Dim swModel As SldWorks.ModelDoc2
                      Dim swSelMgr As SldWorks.SelectionMgr
                      Dim swFeat As SldWorks.Feature
                      Dim swBlockDef As Variant 'SldWorks.SketchBlockDefinition
                      Dim swBlockInst As SldWorks.SketchBlockInstance
                      Dim nbrBlockInst As Integer
                      Dim vBlockInst As Variant
                      Dim BInstPT As MathPoint
                      Dim BVInstPT As Variant
                      Dim BloxDef As Variant
                      Dim Blox As Variant
                      Dim bloxInst As SldWorks.SketchBlockInstance
                      Dim i As Long
                      Dim itr As Integer
                      Sub main()
                      Set swApp = Application.SldWorks
                      Set swModel = swApp.ActiveDoc
                      Set swSelMgr = swModel.SelectionManager
                      Set swFeat = swSelMgr.GetSelectedObject6(1, 0)
                      Set swBlockDef = swFeat.GetSpecificFeature2
                      BloxDef = swModel.SketchManager.GetSketchBlockDefinitions
                      Dim lastSketch As Sketch
                      Debug.Print "Feature type: " & swFeat.GetTypeName
                      nbrBlockInst = swBlockDef.GetInstanceCount
                      Debug.Print "Number of instances of selected block: " & nbrBlockInst
                      Debug.Print "Number of selections: ", swSelMgr.GetSelectedObjectCount2(-1)
                      If nbrBlockInst > 0 Then
                          vBlockInst = swBlockDef.GetInstances
                          For itr = 0 To (nbrBlockInst - 1)
                              Set swBlockInst = vBlockInst(itr)
                              Set BInstPT = swBlockInst.InstancePosition
                              BVInstPT = BInstPT.ArrayData
                              Debug.Print "Name of block instances: " & swBlockInst.Name
                              For Each swBlockDef In BloxDef
                                  If swBlockDef.GetSketch.GetSketchBlockInstanceCount > 0 Then
                                      Blox = swBlockDef.GetSketch.GetSketchBlockInstances
                                      For i = 0 To UBound(Blox)
                                          Set bloxInst = Blox(i)
                                          If bloxInst Is swBlockInst Then
                                              Set swFeat = swBlockDef
                                              Debug.Print "This is an embedded instance inside block definition " & swFeat.Name
                                          End If
                                      Next i
                                  End If
                              Next swBlockDef
                              Debug.Print Math.Round(BVInstPT(0) * 1000, 1) & " / " & Math.Round(BVInstPT(1) * 1000, 1)
                          Next itr
                      End If
                      End Sub
                        • Re: How to check if block instance is nested?
                          Ronny Engmann

                          Hi Josh,

                          really cool, that's what I needed.

                          What I want to do is to give the user a list of blocks / block instances in the active drawing document including some information of these blocks (position, scale factor, angle, ...).

                          You've made a very interesting observation "...that nested block instances only exist once, no matter how many instances of the parent exist...".

                          In that case I think I'll probably use your solution to just check whether an instance belongs to a nested block and then to exclude that from my list.

                          Thank you very much for your help.

                          Kind regards