topic Re: Not able to copy attributes of one block to other using vb.net code in .NET Forum

Not able to copy attributes of one block to other using vb.net code

Anonymous — Thu, 08 Oct 2015 05:00:22 GMT

Hi All,

I am a complete newbie for AutoCad and AutoCad.NET. I am stuck with a problem. I am asking the user to select a block reference which has three attribures namely LINEUP, BAY and HL. Then I am trying to create a copy of it. But the attributes LINEUP and BAY (Values of these) are not being copied. Can You please help me out with this issue.

Original Block With Attributes :

New Block Without Values of the Attributes :

Here is the VB.NET Code :

<CommandMethod("WithAttr2")> _
        Public Sub WithAttr2()
            Dim doc As Document = Application.DocumentManager.MdiActiveDocument
            Dim ed As Editor = Application.DocumentManager.MdiActiveDocument.Editor
            Dim database As Database = ed.Document.Database
            Dim blockName As String
            Dim blockRef1 As BlockReference
            Dim options As PromptEntityOptions = New PromptEntityOptions("\nSelect block reference")
            options.SetRejectMessage("\nSelect only block reference")
            options.AddAllowedClass(GetType(BlockReference), False)

            Dim acSSPrompt As PromptEntityResult = ed.GetEntity(options)

            Using tx As Transaction = database.TransactionManager.StartTransaction()

                Dim blockRef As BlockReference = TryCast(tx.GetObject(acSSPrompt.ObjectId, OpenMode.ForRead), BlockReference)

                Dim block As BlockTableRecord = Nothing
                If (blockRef.IsDynamicBlock) Then

                    'get the real dynamic block name.
                    block = TryCast(tx.GetObject(blockRef.DynamicBlockTableRecord, OpenMode.ForRead), BlockTableRecord)

                Else

                    block = TryCast(tx.GetObject(blockRef.BlockTableRecord, OpenMode.ForRead), BlockTableRecord)
                End If


                If (block <> Nothing) Then
                    Dim sfilter As New SelectionFilter(New TypedValue() {New TypedValue(CInt(DxfCode.Start), "INSERT"), New TypedValue(2, block.Name)})
                    Dim res As PromptSelectionResult = ed.SelectAll(sfilter)
                    If res.Status = PromptStatus.OK Then
                        'display result
                        MsgBox("--->  Selected " & res.Value.Count & " objects", res.Value.Count)
                        Dim Objectset As SelectionSet = res.Value
                        For Each id As ObjectId In Objectset.GetObjectIds()
                            blockRef1 = TryCast(tx.GetObject(id, OpenMode.ForRead), BlockReference)
                            MsgBox(blockRef1.Name)
                            blockName = blockRef1.Name
                            'Dim pt As New Point3d(0, 0, 0)
                            'ACADBlockMgr.InsertBlockWithAtt(blockRef1.Name, pt)
                        Next
                    End If
                End If
                tx.Commit()
            End Using
            Using trans As Transaction = database.TransactionManager.StartTransaction

                Dim blkTable As BlockTable = TryCast(database.BlockTableId.GetObject(OpenMode.ForRead), BlockTable)
                Dim blkRecId As ObjectId = blkTable(blockName)
                MsgBox(blkRecId.ToString())
                If blkRecId <> ObjectId.Null Then
                    Dim blkTableRecord As BlockTableRecord = trans.GetObject(blkRecId, OpenMode.ForRead)
                    Using acBlkRef As New BlockReference(New Point3d(2, 2, 0), blkTableRecord.Id)
                        Dim currentSpaceBlkTableRec As BlockTableRecord = trans.GetObject(database.CurrentSpaceId, OpenMode.ForWrite)
                        currentSpaceBlkTableRec.AppendEntity(acBlkRef)
                        trans.AddNewlyCreatedDBObject(acBlkRef, True)
                        'Check For Attributes
                        If blkTableRecord.HasAttributeDefinitions Then
                            'Add attributes from Block Table Records
                            For Each objId As ObjectId In blkTableRecord
                                Dim dbObj As DBObject = trans.GetObject(objId, OpenMode.ForRead)
                                If TypeOf dbObj Is AttributeDefinition Then
                                    Dim attrDef As AttributeDefinition = dbObj
                                    MsgBox(attrDef.Tag & " " & attrDef.TextString)
                                    If Not attrDef.Constant Then
                                        Using attRef As New AttributeReference
                                            attRef.SetAttributeFromBlock(attrDef, acBlkRef.BlockTransform)
                                            attRef.Position = attRef.Position.TransformBy(acBlkRef.BlockTransform)
                                            attRef.TextString = attrDef.TextString
                                            acBlkRef.AttributeCollection.AppendAttribute(attRef)
                                            trans.AddNewlyCreatedDBObject(attRef, True)
                                        End Using
                                    End If
                                End If
                            Next
                        End If
                    End Using
                End If
                trans.Commit()
            End Using
        End Sub

What am I doing wrong here. Please let me know.

Thanks in Advance,

Abhilash D K

Re: Not able to copy attributes of one block to other using vb.net code

norman.yuan — Thu, 08 Oct 2015 14:03:18 GMT

From your code, I do not see where you do the "copying" attribute (value) from an existing blockReference to the newly inserted BlockRefernce. All your code does is just create all the attributes defined in a BlockTableRecord and uses the default attribute values (i.e. AttributeDefinition.TextString). Obviously, for first 2 tags, the default value is empty and the the third attribute has default value of "*400"

If you need to "copy" the attribute values from another Blockreference, you need to obtain them first, which you did not do. Here is how you do it (pseudo code):

Dim dic As Dictionary(of String, String)

''user select a Block reference, and then get its attribute value

Using (tran As Transaction=....

Dim bref As BlockRefernce = tran.GetObject(....)

For Each id As ObjectId In bref.AttributeCollection

Dim att As AttribueReference=tran.GetObject(....)

''Store attribute value in the Dictionary

If Not dic.ContainsKey(att.Tag.ToUpper()) Then

dic.Add(att.Tag.ToUpper(),att.TextString)

End If

End Using

'' Then go ahead to insert a new BlockReference based on the same BlcokTableRecord

''When creating attribute reference in this new BlcokReference

If Not attrDef.Constant Then
Using attRef As New AttributeReference
attRef.SetAttributeFromBlock(attrDef, acBlkRef.BlockTransform)
attRef.Position = attRef.Position.TransformBy(acBlkRef.BlockTransform)

''attRef.TextString = attrDef.TextString

if dic.ContainsKey(attrDef.Tag.ToUpper()) Then

attrRef.TextString=dic(attrDef.Tag.ToUpper())

Else

attrRef.TextString=attrDef.TextString

End If

acBlkRef.AttributeCollection.AppendAttribute(attRef)
trans.AddNewlyCreatedDBObject(attRef, True)
End Using
End If

HTH

Re: Not able to copy attributes of one block to other using vb.net code

Anonymous — Fri, 09 Oct 2015 04:47:28 GMT

Hi Norman,

Thank you for the reply. I did not know that. Will try to depict your pseudo code into VB.NET and get back to you.

With Regards,

Abhilash D K