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.

VB.NET

Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.Geometry

<CommandMethod("ReloadingExternalReference")> _
Public Sub ReloadingExternalReference()
    ' Get the current database and start a transaction
    Dim acCurDb As Autodesk.AutoCAD.DatabaseServices.Database
    acCurDb = Application.DocumentManager.MdiActiveDocument.Database

    Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction()
        ' Create a reference to a DWG file
        Dim PathName As String = "C:\AutoCAD\Sample\Sheet Sets\Architectural\Res\Exterior Elevations.dwg"
        Dim acXrefId As ObjectId = acCurDb.AttachXref(PathName, "Exterior Elevations")

        ' If a valid reference is created then continue
        If Not acXrefId.IsNull Then
            ' Attach the DWG reference to the current space
            Dim insPt As New Point3d(1, 1, 0)
            Using acBlkRef As New BlockReference(insPt, acXrefId)

                Dim acBlkTblRec As BlockTableRecord
                acBlkTblRec = acTrans.GetObject(acCurDb.CurrentSpaceId, OpenMode.ForWrite)

                acBlkTblRec.AppendEntity(acBlkRef)
                acTrans.AddNewlyCreatedDBObject(acBlkRef, True)
            End Using

            MsgBox("The external reference is attached.")

            Using acXrefIdCol As New ObjectIdCollection
                acXrefIdCol.Add(acXrefId)

                acCurDb.ReloadXrefs(acXrefIdCol)
            End Using

            MsgBox("The external reference is reloaded.")
        End If

        ' Save the new objects to the database
        acTrans.Commit()

        ' Dispose of the transaction
    End Using
End Sub

C#

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
    }
}

VBA/ActiveX Code Reference

Sub ReloadingExternalReference()
    ' Define external reference to be inserted
    Dim xrefInserted As AcadExternalReference
    Dim insertionPnt(0 To 2) As Double
    Dim PathName As String
    insertionPnt(0) = 1
    insertionPnt(1) = 1
    insertionPnt(2) = 0
    PathName = "C:\AutoCAD\Sample\Sheet Sets\Architectural\Res\Exterior Elevations.dwg"
 
    ' Add the external reference to the block
    Set xrefInserted = ThisDrawing.ActiveLayout.Block. _
        AttachExternalReference(PathName, "Exterior Elevations", insertionPnt, 1, 1, 1, 0, False)

    MsgBox "The external reference is attached."
 
    ' Reload the external reference definition
    ThisDrawing.Blocks.Item(xrefInserted.name).Reload
    MsgBox "The external reference is reloaded."
End Sub