Turn Layers On and Off
 
 
 

Layers in which are turned off are regenerated with the drawing but are not displayed or plotted. By turning layers off, you avoid regenerating the drawing every time you thaw a layer. When you turn a layer on that has been turned off, AutoCAD redraws the objects on that layer.

Use the IsOff property on the Layer Table Record object that represents the layer you want to turn on or off. If you input a value of TRUE, the layer is turned off. If you input a value of FALSE, the layer is turned on.

Turn off a layer

This example creates a new layer and turns it off, and then adds a circle to the layer so that the circle is no longer visible.

VB.NET

Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.Geometry
 
<CommandMethod("TurnLayerOff")> _
Public Sub TurnLayerOff()
  '' 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
 
      '' Turn the layer off
      acLyrTblRec.IsOff = True
 
      '' Open the Block table for read
      Dim acBlkTbl As BlockTable
      acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId, _
                                   OpenMode.ForRead)
 
      '' Open the Block table record Model space for write
      Dim acBlkTblRec As BlockTableRecord
      acBlkTblRec = acTrans.GetObject(acBlkTbl(BlockTableRecord.ModelSpace), _
                                      OpenMode.ForWrite)
 
      '' Create a circle object
      Dim acCirc As Circle = New Circle()
      acCirc.Center = New Point3d(2, 2, 0)
      acCirc.Radius = 1
      acCirc.Layer = sLayerName
 
      acBlkTblRec.AppendEntity(acCirc)
      acTrans.AddNewlyCreatedDBObject(acCirc, True)
 
      '' Save the changes and dispose of the transaction
      acTrans.Commit()
  End Using
End Sub

C#

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.Geometry;
 
[CommandMethod("TurnLayerOff")]
public static void TurnLayerOff()
{
  // 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;
      }
 
      // Turn the layer off
      acLyrTblRec.IsOff = true;
 
      // 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 object
      Circle acCirc = new Circle();
      acCirc.Center = new Point3d(2, 2, 0);
      acCirc.Radius = 1;
      acCirc.Layer = sLayerName;
 
      acBlkTblRec.AppendEntity(acCirc);
      acTrans.AddNewlyCreatedDBObject(acCirc, true);
 
      // Save the changes and dispose of the transaction
      acTrans.Commit();
  }
}
VBA/ActiveX Code Reference