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.
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.
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
}
}
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
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