public static void CreateLayerIFNonExisting(string layername)
{
Transaction trans = Active.StartTransaction();
var layerTable = (LayerTable)trans.GetObject(Database.LayerTableId, OpenMode.ForRead);
if (!layerTable.Has(layername))
{
var newLayer = new LayerTableRecord()
{
Name = layername
};
layerTable.UpgradeOpen();
layerTable.Add(newLayer);
trans.AddNewlyCreatedDBObject(newLayer, true);
}
trans.Commit();
}
public static void DeleteAllEntitiesOnLayer(string layername)
{
using (Transaction trans = Active.StartTransaction()) {
TypedValue[] selectionCriteria =
new TypedValue[] { new TypedValue((int)DxfCode.LayerName, layername) };
SelectionFilter filter = new SelectionFilter(selectionCriteria);
PromptSelectionResult result = Active.Editor.SelectAll(filter);
if (result.Status == PromptStatus.OK)
{
SelectionSet set = result.Value;
ObjectId[] ids = set.GetObjectIds();
foreach (ObjectId id in ids)
{
id.GetObject(OpenMode.ForWrite).Erase();
}
}
trans.Commit();
}
}