Dynamic Block - Read Properties of Visible Entities

[Hugh_Compton]

I am trying to access the entties in the Dynamic Blocks of a drawing.  My code crashes.....

<CommandMethod("DTest2")> _
    Public Sub DynamicBlockgetValuesofVisibleEntites()
        Dim doc As Document = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument
        Dim db As Database = doc.Database
        Dim ed As Editor = doc.Editor
        Dim i As Integer = 0

        Using trx As Transaction = db.TransactionManager.StartTransaction()

            Dim bt As BlockTable = TryCast(db.BlockTableId.GetObject(OpenMode.ForRead), BlockTable)
            For Each objId As ObjectId In bt
                Dim btr As BlockTableRecord = DirectCast(objId.GetObject(OpenMode.ForRead), BlockTableRecord)

                If btr.IsDynamicBlock Then

                    Dim brefObjidColl As ObjectIdCollection = btr.GetBlockReferenceIds(True, True)
                    Dim anonObjIdsColl As ObjectIdCollection = btr.GetAnonymousBlockIds()

                    For Each anonObjId As ObjectId In anonObjIdsColl
                        Dim btrAnon As BlockTableRecord = DirectCast(anonObjId.GetObject(OpenMode.ForRead), BlockTableRecord)
                        Dim ObjidColl As ObjectIdCollection = btrAnon.GetBlockReferenceIds(True, True)
                        For Each Id As ObjectId In ObjidColl
                            brefObjidColl.Add(Id)
                        Next
                    Next

                    For Each brefObjId As ObjectId In brefObjidColl
                        Dim bref As Autodesk.AutoCAD.DatabaseServices.BlockReference = TryCast(brefObjId.GetObject(OpenMode.ForWrite), Autodesk.AutoCAD.DatabaseServices.BlockReference)

                        Dim objs As DBObjectCollection = Nothing

                        bref.UpgradeOpen()
                        'bref.ConvertToStaticBlock() ' Converts block reference to a static anonymous block
                        bref.Explode(objs) ' This is being exploded in memory only - there is no Commit line


                        For Each obj As Autodesk.AutoCAD.DatabaseServices.DBObject In objs

                            Dim ent As Autodesk.AutoCAD.DatabaseServices.Entity = CType(obj, Autodesk.AutoCAD.DatabaseServices.Entity)

                            If ent.Visible Then ' this is prob not necessary since the block has been exploded but it doesn't do any harm

                                i += 1

                            End If

                        Next obj

                    Next
                End If
            Next
            ed.WriteMessage("There are " & i & " entities in the dynamic blocks")
            trx.Commit()
        End Using
    End Sub 

[philippe.leefsma]

Hi

You need to dispose those exploded DBObjects, they will leak otherwise...

Take a look at the following blog post, you may find it useful:

http://adndevblog.typepad.com/autocad/2012/05/accessing-visible-entities-in-a-dynamic-block.html

Philippe.

[Hugh_Compton]

Dim ids_diff As New ObjectIdCollection
    <CommandMethod("DBINFO", CommandFlags.Modal)> _
    Public Sub Apply_Information_To_Dynamic_Blocks()
        Dim doc As Document = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument
        Dim db As Database = doc.Database
        Dim ed As Editor = doc.Editor

 

        Using tr As Transaction = db.TransactionManager.StartTransaction
            Dim ms As BlockTableRecord = tr.GetObject(SymbolUtilityServices.GetBlockModelSpaceId(db), OpenMode.ForWrite)

            Dim intCount As Integer = 0

            For Each id As ObjectId In ms
                Dim br As Autodesk.AutoCAD.DatabaseServices.BlockReference = TryCast(tr.GetObject(id, OpenMode.ForWrite), Autodesk.AutoCAD.DatabaseServices.BlockReference)
                If br Is Nothing Then Continue For
                If Not br.IsDynamicBlock Then Continue For
                 
                 

                ids_diff.Clear()
                AddHandler db.ObjectAppended, AddressOf db_ObjectAppended
                br.ExplodeToOwnerSpace()
                RemoveHandler db.ObjectAppended, AddressOf db_ObjectAppended

                For Each id2 As ObjectId In ids_diff
                    'ed.WriteMessage(vbNewLine & "Object Exploded to Modelspace: " & id2.ObjectClass.Name)
                    If id2.ObjectClass.Name = "AcDb3dSolid" Then ' This is the 3D solid that was displayed for the dynamic block
                        ‘ Do something here to the 3D Solids 
                    End If

                    ' Now dispose of the entities
                    Try
                        Dim ent As Autodesk.AutoCAD.DatabaseServices.Entity = tr.GetObject(id2, OpenMode.ForWrite, False, False)
                        ent.Erase()
                        ent.Dispose()
                    Catch
                        ' not able to cast ObjectID as an entity
                    End Try
                Next

                ' Now do something here to the dynamic block if necessary
                
                intCount += 1
            Next
            ed.WriteMessage(vbNewLine & intCount.ToString & " Dynamic Blocks have had information added successfully from the visible 3DSolid within the block, apart from 'Notes'")
            tr.Commit()
            tr.Dispose()
        End Using

    End Sub
    Public Sub db_ObjectAppended(s As Object, e As ObjectEventArgs)
        ids_diff.Add(e.DBObject.ObjectId)
    End Sub

Thanks for the link Philippe, I think I have it sorted now (see code above).  I believe that I have disposed of the DBObjects......

[philippe.leefsma]

Great! Please mark as solved if the answer helped.

Thank you,

Philippe.