Freeze and Thaw Layers

You can freeze layers to speed up display changes, improve object selection performance, and reduce regeneration time for complex drawings. AutoCAD does not display, plot, or regenerate objects on frozen layers. Freeze the layers that you will not be working with for long periods of time. When you “thaw” a frozen layer, AutoCAD regenerates and displays the objects on that layer.

Use the IsFrozen property to freeze or thaw a layer. If you input a value of TRUE, the layer is frozen. If you input a value of FALSE, the layer is thawed.

Freeze a layer

This example creates a new layer called “ABC” and then freezes the layer.

VB.NET

Imports Autodesk.AutoCAD.Runtime

Imports Autodesk.AutoCAD.ApplicationServices

Imports Autodesk.AutoCAD.DatabaseServices

<CommandMethod("FreezeLayer")> _

Public Sub FreezeLayer()

  '' Get the current document and database

  Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument

  Dim acCurDb As Database = acDoc.Database

  '' Start a transaction

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

      '' Open the Layer table for read

      Dim acLyrTbl As LayerTable

      acLyrTbl = acTrans.GetObject(acCurDb.LayerTableId, _

                                   OpenMode.ForRead)

      Dim sLayerName As String = "ABC"

      Dim acLyrTblRec As LayerTableRecord

      If acLyrTbl.Has(sLayerName) = False Then

          acLyrTblRec = New LayerTableRecord()

          '' Assign the layer a name

          acLyrTblRec.Name = sLayerName

          '' Upgrade the Layer table for write

          acLyrTbl.UpgradeOpen()

          '' Append the new layer to the Layer table and the transaction

          acLyrTbl.Add(acLyrTblRec)

          acTrans.AddNewlyCreatedDBObject(acLyrTblRec, True)

      Else

          acLyrTblRec = acTrans.GetObject(acLyrTbl(sLayerName), _

                                          OpenMode.ForWrite)

      End If

      '' Freeze the layer

      acLyrTblRec.IsFrozen = True

      '' Save the changes and dispose of the transaction

      acTrans.Commit()

  End Using

End Sub

using Autodesk.AutoCAD.Runtime;

using Autodesk.AutoCAD.ApplicationServices;

using Autodesk.AutoCAD.DatabaseServices;

[CommandMethod("FreezeLayer")]

public static void FreezeLayer()

  // 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 Layer table for read

      LayerTable acLyrTbl;

      acLyrTbl = acTrans.GetObject(acCurDb.LayerTableId,

                                   OpenMode.ForRead) as LayerTable;

      string sLayerName = "ABC";

      LayerTableRecord acLyrTblRec;

      if (acLyrTbl.Has(sLayerName) == false)

          acLyrTblRec = new LayerTableRecord();

          // Assign the layer a name

          acLyrTblRec.Name = sLayerName;

          // Upgrade the Layer table for write

          acLyrTbl.UpgradeOpen();

          // Append the new layer to the Layer table and the transaction

          acLyrTbl.Add(acLyrTblRec);

          acTrans.AddNewlyCreatedDBObject(acLyrTblRec, true);

      else

          acLyrTblRec = acTrans.GetObject(acLyrTbl[sLayerName],

                                          OpenMode.ForWrite) as LayerTableRecord;

      // Freeze the layer

      acLyrTblRec.IsFrozen = true;

      // Save the changes and dispose of the transaction

      acTrans.Commit();

VBA/ActiveX Code Reference