I'm trying to create a custom command for a rectangular array. As a starting point I've just copied all the code from the AutoCad .Net Developers Guide (see large block of code below) and pasted it straight into Visual Studio, however it's picking up an error (see image). Can someone help me out with correcting this. It's strange that I'm getting this error even through the code is directly from the Guide.

Thanks in advance.

<CommandMethod("RectangularArrayObject")>
    Public Shared Sub RectangularArrayObject()
        '' Get the current document and database
        Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument
        Dim acCurDb As Database = acDoc.Database
        '' Start a transaction
        Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction()
            '' Open the Block table record for read
            Dim acBlkTbl As BlockTable
            acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId,
                                               OpenMode.ForRead)
            '' Open the Block table record Model space for write
            Dim acBlkTblRec As BlockTableRecord
            acBlkTblRec = acTrans.GetObject(acBlkTbl(BlockTableRecord.ModelSpace),
                                                  OpenMode.ForWrite)
            '' Create a circle that is at 2,2 with a radius of 0.5
            Dim acCirc As Circle = New Circle()
            acCirc.SetDatabaseDefaults()
            acCirc.Center = New Point3d(2, 2, 0)
            acCirc.Radius = 0.5
            '' Add the new object to the block table record and the transaction
            acBlkTblRec.AppendEntity(acCirc)
            acTrans.AddNewlyCreatedDBObject(acCirc, True)
            '' Create a rectangular array with 5 rows and 5 columns
            Dim nRows As Integer = 5
            Dim nColumns As Integer = 5
            '' Set the row and column offsets along with the base array angle
            Dim dRowOffset As Double = 1
            Dim dColumnOffset As Double = 1
            Dim dArrayAng As Double = 0
            '' Get the angle from X for the current UCS
            Dim curUCSMatrix As Matrix3d = acDoc.Editor.CurrentUserCoordinateSystem
            Dim curUCS As CoordinateSystem3d = curUCSMatrix.CoordinateSystem3d
            Dim acVec2dAng As Vector2d = New Vector2d(curUCS.Xaxis.X,
                                                            curUCS.Xaxis.Y)
            '' If the UCS is rotated, adjust the array angle accordingly
            dArrayAng = dArrayAng   acVec2dAng.Angle
            '' Use the upper-left corner of the objects extents for the array base point
            Dim acExts As Extents3d = acCirc.Bounds.GetValueOrDefault()
            Dim acPt2dArrayBase As Point2d = New Point2d(acExts.MinPoint.X,
                                                               acExts.MaxPoint.Y)
            '' Track the objects created for each column
            Dim acDBObjCollCols As DBObjectCollection = New DBObjectCollection()
            acDBObjCollCols.Add(acCirc)
            '' Create the number of objects for the first column
            Dim nColumnsCount As Integer = 1
            While (nColumns > nColumnsCount)
                Dim acEntClone As Entity = acCirc.Clone()
                acDBObjCollCols.Add(acEntClone)
                '' Caclucate the new point for the copied object (move)
                Dim acPt2dTo As Point2d = PolarPoints(acPt2dArrayBase,
                                                      dArrayAng,
                                                      dColumnOffset * nColumnsCount)
                Dim acVec2d As Vector2d = acPt2dArrayBase.GetVectorTo(acPt2dTo)
                Dim acVec3d As Vector3d = New Vector3d(acVec2d.X, acVec2d.Y, 0)
                acEntClone.TransformBy(Matrix3d.Displacement(acVec3d))
                acBlkTblRec.AppendEntity(acEntClone)
                acTrans.AddNewlyCreatedDBObject(acEntClone, True)
                nColumnsCount = nColumnsCount   1
            End While
            '' Set a value in radians for 90 degrees
            Dim dAng As Double = Math.PI / 2
            '' Track the objects created for each row and column
            Dim acDBObjCollLvls As DBObjectCollection = New DBObjectCollection()
            For Each acObj As DBObject In acDBObjCollCols
                acDBObjCollLvls.Add(acObj)
            Next
            '' Create the number of objects for each row
            For Each acEnt As Entity In acDBObjCollCols
                Dim nRowsCount As Integer = 1
                While (nRows > nRowsCount)
                    Dim acEntClone As Entity = acEnt.Clone()
                    acDBObjCollLvls.Add(acEntClone)
                    '' Caclucate the new point for the copied object (move)
                    Dim acPt2dTo As Point2d = PolarPoints(acPt2dArrayBase,
                                                          dArrayAng   dAng,
                                                          dRowOffset * nRowsCount)
                    Dim acVec2d As Vector2d = acPt2dArrayBase.GetVectorTo(acPt2dTo)
                    Dim acVec3d As Vector3d = New Vector3d(acVec2d.X, acVec2d.Y, 0)
                    acEntClone.TransformBy(Matrix3d.Displacement(acVec3d))
                    acBlkTblRec.AppendEntity(acEntClone)
                    acTrans.AddNewlyCreatedDBObject(acEntClone, True)
                    nRowsCount = nRowsCount   1
                End While
            Next
            '' Save the new objects to the database
            acTrans.Commit()
        End Using
    End Sub

CodePudding user response：

This error must be due to something else than the code, probably the general context (AutoCAD version, referenced libraries, ...). In any case, this code example from the AutoCad .Net Developers Guide is, as often, not so well written. In the case of an entity that we are sure has a valid Extend3d (a circle of radius 0.5), using Entity.GeometricExtents is much cheaper than using Drawable.Bounds.

Dim acExts As Extents3d = acCirc.GeometricExtents