Imports Autodesk.AutoCAD.Runtime

Imports Autodesk.AutoCAD.ApplicationServices

Imports Autodesk.AutoCAD.DatabaseServices

Imports Autodesk.AutoCAD.Geometry

<CommandMethod("EditHatchPatternScale")> _

Public Sub EditHatchPatternScale()

  '' 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 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 object for the boundary of the hatch

      Dim acCirc As Circle = New Circle()

      acCirc.Center = New Point3d(5, 3, 0)

      acCirc.Radius = 3

      acBlkTblRec.AppendEntity(acCirc)

      acTrans.AddNewlyCreatedDBObject(acCirc, True)

      '' Adds the arc and line to an object id collection

      Dim acObjIdColl As ObjectIdCollection = New ObjectIdCollection()

      acObjIdColl.Add(acCirc.ObjectId)

      '' Create the hatch object and append it to the block table record

      Dim acHatch As Hatch = New Hatch()

      acBlkTblRec.AppendEntity(acHatch)

      acTrans.AddNewlyCreatedDBObject(acHatch, True)

      '' Set the properties of the hatch object

      '' Associative must be set after the hatch object is appended to the 

      '' block table record and before AppendLoop

      acHatch.SetHatchPattern(HatchPatternType.PreDefined, "ANSI31")

      acHatch.Associative = True

      acHatch.AppendLoop(HatchLoopTypes.Outermost, acObjIdColl)

      '' Evaluate the hatch

      acHatch.EvaluateHatch(True)

      '' Increase the pattern scale by 2 and re-evaluate the hatch

      acHatch.PatternScale = acHatch.PatternScale + 2

      acHatch.SetHatchPattern(acHatch.PatternType, acHatch.PatternName)

      acHatch.EvaluateHatch(True)

      '' Save the new object to the database

      acTrans.Commit()

  End Using

End Sub

using Autodesk.AutoCAD.Runtime;

using Autodesk.AutoCAD.ApplicationServices;

using Autodesk.AutoCAD.DatabaseServices;

using Autodesk.AutoCAD.Geometry;

[CommandMethod("EditHatchPatternScale")]

public static void EditHatchPatternScale()

{

  // Get the current document and database

  Document acDoc = Application.DocumentManager.MdiActiveDocument;

  Database acCurDb = acDoc.Database;

  // Start a transaction

  using (Transaction acTrans = acCurDb.TransactionManager.StartTransaction())

  {

      // Open the Block table for read

      BlockTable acBlkTbl;

      acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId,

                                   OpenMode.ForRead) as BlockTable;

      // Open the Block table record Model space for write

      BlockTableRecord acBlkTblRec;

      acBlkTblRec = acTrans.GetObject(acBlkTbl[BlockTableRecord.ModelSpace],

                                      OpenMode.ForWrite) as BlockTableRecord;

      // Create a circle object for the boundary of the hatch

      Circle acCirc = new Circle();

      acCirc.Center = new Point3d(5, 3, 0);

      acCirc.Radius = 3;

      acBlkTblRec.AppendEntity(acCirc);

      acTrans.AddNewlyCreatedDBObject(acCirc, true);

      // Adds the arc and line to an object id collection

      ObjectIdCollection acObjIdColl = new ObjectIdCollection();

      acObjIdColl.Add(acCirc.ObjectId);

      // Create the hatch object and append it to the block table record

      Hatch acHatch = new Hatch();

      acBlkTblRec.AppendEntity(acHatch);

      acTrans.AddNewlyCreatedDBObject(acHatch, true);

      // Set the properties of the hatch object

      // Associative must be set after the hatch object is appended to the 

      // block table record and before AppendLoop

      acHatch.SetHatchPattern(HatchPatternType.PreDefined, "ANSI31");

      acHatch.Associative = true;

      acHatch.AppendLoop(HatchLoopTypes.Outermost, acObjIdColl);

      // Evaluate the hatch

      acHatch.EvaluateHatch(true);

      // Increase the pattern scale by 2 and re-evaluate the hatch

      acHatch.PatternScale = acHatch.PatternScale + 2;

      acHatch.SetHatchPattern(acHatch.PatternType, acHatch.PatternName);

      acHatch.EvaluateHatch(true);

      // Save the new object to the database

      acTrans.Commit();

  }

}