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.
This example creates a new layer called “ABC” and then freezes the layer.
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";
if (acLyrTbl.Has(sLayerName) == false)
{
using (LayerTableRecord acLyrTblRec = new LayerTableRecord())
{
// Assign the layer a name
acLyrTblRec.Name = sLayerName;
// Freeze the layer
acLyrTblRec.IsFrozen = true;
// Upgrade the Layer table for write
acTrans.GetObject(acCurDb.LayerTableId, OpenMode.ForWrite);
// Append the new layer to the Layer table and the transaction
acLyrTbl.Add(acLyrTblRec);
acTrans.AddNewlyCreatedDBObject(acLyrTblRec, true);
}
}
else
{
LayerTableRecord 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();
}
}