Imports Autodesk.AutoCAD.Runtime

Imports Autodesk.AutoCAD.ApplicationServices

Imports Autodesk.AutoCAD.DatabaseServices

Imports Autodesk.AutoCAD.Geometry

<CommandMethod("AddSpline")> _

Public Sub AddSpline()

  '' 获得当前文档和数据库   Get the current document and database

  Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument

  Dim acCurDb As Database = acDoc.Database

  ''启动一个事务   Start a transaction

  Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction()

      '' 以只读方式打开块表   Open the Block table for read

      Dim acBlkTbl As BlockTable

      acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId, OpenMode.ForRead)

      '' 以写方式打开模型空间块表记录   Open the Block table record Model space for write

      Dim acBlkTblRec As BlockTableRecord

      acBlkTblRec = acTrans.GetObject(acBlkTbl(BlockTableRecord.ModelSpace), _

                                      OpenMode.ForWrite)

      '' 定义样条曲线的固定点   Define the fit points for the spline

      Dim ptColl As Point3dCollection = New Point3dCollection()

      ptColl.Add(New Point3d(0, 0, 0))

      ptColl.Add(New Point3d(5, 5, 0))

      ptColl.Add(New Point3d(10, 0, 0))

      ''从点(0.5,0.5,0)获得三维矢量    Get a 3D vector from the point (0.5,0.5,0)

      Dim vecTan As Vector3d = New Point3d(0.5, 0.5, 0).GetAsVector

      '' Create a spline through (0, 0, 0), (5, 5, 0), and (10, 0, 0) with a

      '' start and end tangency of (0.5, 0.5, 0.0)

      Dim acSpline As Spline = New Spline(ptColl, vecTan, vecTan, 4, 0.0)

      acSpline.SetDatabaseDefaults()

      '' 添加新对象到块表记录和事务中   Add the new object to the block table record and the transaction

      acBlkTblRec.AppendEntity(acSpline)

      acTrans.AddNewlyCreatedDBObject(acSpline, True)

      '' 保存新对象到数据库中   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("AddSpline")]

public static void AddSpline()

{

  // 获得当前文档和数据库   Get the current document and database

  Document acDoc = Application.DocumentManager.MdiActiveDocument;

  Database acCurDb = acDoc.Database;

  // 启动一个事务  Start a transaction

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

  {

      // 以只读方式打开块表   Open the Block table for read

      BlockTable acBlkTbl;

      acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId,

                                   OpenMode.ForRead) as BlockTable;

      // 以写方式打开模型空间块表记录   Open the Block table record Model space for write

      BlockTableRecord acBlkTblRec;

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

                                      OpenMode.ForWrite) as BlockTableRecord;

      // 定义样条曲线的固定点   Define the fit points for the spline

      Point3dCollection ptColl = new Point3dCollection();

      ptColl.Add(new Point3d(0, 0, 0));

      ptColl.Add(new Point3d(5, 5, 0));

      ptColl.Add(new Point3d(10, 0, 0));

      //从点(0.5,0.5,0)获得三维矢量    Get a 3D vector from the point (0.5,0.5,0)

      Vector3d vecTan = new Point3d(0.5, 0.5, 0).GetAsVector();

      // Create a spline through (0, 0, 0), (5, 5, 0), and (10, 0, 0) with a

      // start and end tangency of (0.5, 0.5, 0.0)

      Spline acSpline = new Spline(ptColl, vecTan, vecTan, 4, 0.0);

      acSpline.SetDatabaseDefaults();

      // 添加新对象到块表记录和事务中   Add the new object to the block table record and the transaction

      acBlkTblRec.AppendEntity(acSpline);

      acTrans.AddNewlyCreatedDBObject(acSpline, true);

      // 保存新的直线到数据库中    Save the new line to the database

      acTrans.Commit();

  }

}