Reload Xrefs (.NET)

If someone modifies an externally referenced drawing while you are working on the host drawing to which that xref is attached, you can update that xref drawing using the Reload method. When you reload, the selected xref drawing is updated in your host drawing. Also, if you have unloaded an xref, you can choose to reload that externally referenced drawing at any time.

Reload an xref definition

This example attaches an external reference and then reloads the external reference. This example uses the Exterior Elevations.dwg file found in the Sample directory. If you do not have this image, or if it is located in a different directory, insert a valid path and file name.

C# Example

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.Geometry;

[CommandMethod("ReloadingExternalReference")]
public void ReloadingExternalReference()
{
    // Get the current database and start a transaction
    Database acCurDb;
    acCurDb = Application.DocumentManager.MdiActiveDocument.Database;

    using (Transaction acTrans = acCurDb.TransactionManager.StartTransaction())
    {
        // Create a reference to a DWG file
        string PathName = "C:\\AutoCAD\\Sample\\Sheet Sets\\Architectural\\Res\\Exterior Elevations.dwg";
        ObjectId acXrefId = acCurDb.AttachXref(PathName, "Exterior Elevations");

        // If a valid reference is created then continue
        if (!acXrefId.IsNull)
        {
            // Attach the DWG reference to the current space
            Point3d insPt = new Point3d(1, 1, 0);
            using (BlockReference acBlkRef = new BlockReference(insPt, acXrefId))
            {
                BlockTableRecord acBlkTblRec;
                acBlkTblRec = acTrans.GetObject(acCurDb.CurrentSpaceId, OpenMode.ForWrite) as BlockTableRecord;

                acBlkTblRec.AppendEntity(acBlkRef);
                acTrans.AddNewlyCreatedDBObject(acBlkRef, true);
            }

            Application.ShowAlertDialog("The external reference is attached.");

            using (ObjectIdCollection acXrefIdCol = new ObjectIdCollection())
            {
                acXrefIdCol.Add(acXrefId);

                acCurDb.ReloadXrefs(acXrefIdCol);
            }

            Application.ShowAlertDialog("The external reference is reloaded.");
        }

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

        // Dispose of the transaction
    }
}