Copy an Object (.NET)

To copy an object, use the Clone method provided for that object. This method creates a new object that is a duplicate of the original object in the same database. Once the duplicate object is created, you can then modify it prior to adding or appending it to the database. If you do not transform the object or change its position, the new object will be located in the same position as the original. In addition to creating a new object with the Clone method, the CopyFrom method can be used to copy properties from one object to another object.

If you have a large number of objects you might want to copy, you can add each of the object ids to an ObjectIdCollection object and then iterate each object id in the collection. As you iterate each object id, you can then use the Clone function after the open is open for read and then add or append the new object to the database.

Copy a single object

The following example creates a new circle and then creates a direct copy of the circle to create a second circle.

C# Example

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.Geometry;
 
[CommandMethod("SingleCopy")]
public static void SingleCopy()
{
    // 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 that is at 2,3 with a radius of 4.25
        using (Circle acCirc = new Circle())
        {
            acCirc.Center = new Point3d(2, 3, 0);
            acCirc.Radius = 4.25;

            // Add the new object to the block table record and the transaction
            acBlkTblRec.AppendEntity(acCirc);
            acTrans.AddNewlyCreatedDBObject(acCirc, true);

            // Create a copy of the circle and change its radius
            Circle acCircClone = acCirc.Clone() as Circle;
            acCircClone.Radius = 1;

            // Add the cloned circle
            acBlkTblRec.AppendEntity(acCircClone);
            acTrans.AddNewlyCreatedDBObject(acCircClone, true);
        }

        // Save the new object to the database
        acTrans.Commit();
    }
}

Copy multiple objects

The following example uses an ObjectIdCollection object to track the objects that should be copied. Once the object ids are added to the collection, the collection is iterated and new objects are created by using the Clone method and then are added to Model space.

C# Example

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.Geometry;
 
[CommandMethod("MultipleCopy")]
public static void MultipleCopy()
{
    // 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 that is at (0,0,0) with a radius of 5
        using (Circle acCirc1 = new Circle())
        {
            acCirc1.Center = new Point3d(0, 0, 0);
            acCirc1.Radius = 5;

            // Add the new object to the block table record and the transaction
            acBlkTblRec.AppendEntity(acCirc1);
            acTrans.AddNewlyCreatedDBObject(acCirc1, true);

            // Create a circle that is at (0,0,0) with a radius of 7
            using (Circle acCirc2 = new Circle())
            {
                acCirc2.Center = new Point3d(0, 0, 0);
                acCirc2.Radius = 7;

                // Add the new object to the block table record and the transaction
                acBlkTblRec.AppendEntity(acCirc2);
                acTrans.AddNewlyCreatedDBObject(acCirc2, true);

                // Add all the objects to clone
                DBObjectCollection acDBObjColl = new DBObjectCollection();
                acDBObjColl.Add(acCirc1);
                acDBObjColl.Add(acCirc2);

                foreach (Entity acEnt in acDBObjColl)
                {
                    Entity acEntClone;
                    acEntClone = acEnt.Clone() as Entity;
                    acEntClone.ColorIndex = 1;

                    // Create a matrix and move each copied entity 15 units
                    acEntClone.TransformBy(Matrix3d.Displacement(new Vector3d(15, 0, 0)));

                    // Add the cloned object
                    acBlkTblRec.AppendEntity(acEntClone);
                    acTrans.AddNewlyCreatedDBObject(acEntClone, true);
                }
            }
        }

        // Save the new object to the database
        acTrans.Commit();
    }
}