implemented CmdDeleteUnusedRefPlanes

BcSamples.txt

@@ -913,3 +913,11 @@ LargeImage:
 Image:
 C:\a\lib\revit\2014\bc\BuildingCoder\BuildingCoder\bin\Debug\BuildingCoder.dll
 BuildingCoder.CmdRollingOffset # version 2014.0.106.0
+
+ADN Bc N-Z
+Delete Unused Reference Planes
+Delete unnamed non-hosting reference planes
+LargeImage:
+Image:
+C:\a\lib\revit\2014\bc\BuildingCoder\BuildingCoder\bin\Debug\BuildingCoder.dll
+BuildingCoder.CmdDeleteUnusedRefPlanes # version 2014.0.107.0

BuildingCoder/BuildingCoder/BuildingCoder.csproj

@@ -136,6 +136,7 @@
     <Compile Include="CmdMepElementShape.cs" />
     <Compile Include="CmdMidCurve.cs" />
     <Compile Include="CmdMirror.cs" />
+    <Compile Include="CmdDeleteUnusedRefPlanes.cs" />
     <Compile Include="CmdRollingOffset.cs" />
     <Compile Include="CmdRoomNeighbours.cs" />
     <Compile Include="CmdNestedFamilies.cs" />

BuildingCoder/BuildingCoder/CmdDeleteUnusedRefPlanes.cs

@@ -0,0 +1,195 @@
+#region Header
+//
+// CmdDeleteUnusedRefPlanes.cs - delete unnamed non-hosting reference planes
+//
+// Copyright (C) 2014 by Jeremy Tammik, Autodesk Inc. All rights reserved.
+//
+#endregion // Header
+
+#region Namespaces
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Diagnostics;
+using Autodesk.Revit.ApplicationServices;
+using Autodesk.Revit.Attributes;
+using Autodesk.Revit.DB;
+using Autodesk.Revit.DB.Plumbing;
+using Autodesk.Revit.UI;
+using Autodesk.Revit.UI.Selection;
+#endregion // Namespaces
+
+namespace BuildingCoder
+{
+  /// <summary>
+  /// Delete all reference planes that have not been 
+  /// named and are not hosting any elements.
+  /// In other words, check whether the reference 
+  /// plane has been named.
+  /// If not, check whether it hosts any elements.
+  /// If not, delete it.
+  /// Actually, to check whether it hosts any 
+  /// elements, we delete it temporarily anyway, as
+  /// described in
+  /// Object Relationships http://thebuildingcoder.typepad.com/blog/2010/03/object-relationships.html
+  /// Object Relationships in VB http://thebuildingcoder.typepad.com/blog/2010/03/object-relationships-in-vb.html
+  /// Temporary Transaction Trick Touchup http://thebuildingcoder.typepad.com/blog/2012/11/temporary-transaction-trick-touchup.html
+  /// The deletion returns the number of elements 
+  /// deleted. If this number is greater than one (the 
+  /// ref plane itself), it hosted something. In that 
+  /// case, roll back the transaction and do not delete.
+  /// </summary>
+  [Transaction( TransactionMode.Manual )]
+  class CmdDeleteUnusedRefPlanes : IExternalCommand
+  {
+    static int _i = 0;
+
+    /// <summary>
+    /// Delete the given reference plane 
+    /// if it is not hosting anything.
+    /// </summary>
+    /// <returns>True if the given reference plane
+    /// was in fact deleted, else false.</returns>
+    bool DeleteIfNotHosting( ReferencePlane rp )
+    {
+      bool rc = false;
+
+      Document doc = rp.Document;
+
+      using( Transaction tx = new Transaction( doc ) )
+      {
+        tx.Start( "Delete ReferencePlane "
+          + ( ++_i ).ToString() );
+
+        // Deletion simply fails if the reference 
+        // plane hosts anything. If so, the return 
+        // value ids collection is null.
+        // In Revit 2014, in that case, the call 
+        // throws an exception "ArgumentException: 
+        // ElementId cannot be deleted."
+
+        try
+        {
+          ICollection<ElementId> ids = doc.Delete(
+            rp.Id );
+
+          tx.Commit();
+          rc = true;
+        }
+        catch( ArgumentException )
+        {
+          tx.RollBack();
+        }
+      }
+      return rc;
+    }
+
+    public Result Execute(
+      ExternalCommandData commandData,
+      ref string message,
+      ElementSet elements )
+    {
+      UIApplication uiapp = commandData.Application;
+      UIDocument uidoc = uiapp.ActiveUIDocument;
+      Application app = uiapp.Application;
+      Document doc = uidoc.Document;
+
+      // Construct a parameter filter to get only 
+      // unnamed reference planes, i.e. reference 
+      // planes whose name equals the empty string:
+
+      BuiltInParameter bip
+        = BuiltInParameter.DATUM_TEXT;
+
+      ParameterValueProvider provider
+        = new ParameterValueProvider(
+          new ElementId( bip ) );
+
+      FilterStringRuleEvaluator evaluator
+        = new FilterStringEquals();
+
+      FilterStringRule rule = new FilterStringRule(
+        provider, evaluator, "", false );
+
+      ElementParameterFilter filter
+        = new ElementParameterFilter( rule );
+
+      FilteredElementCollector col
+        = new FilteredElementCollector( doc )
+          .OfClass( typeof( ReferencePlane ) )
+          .WherePasses( filter );
+
+      int n = 0;
+      int nDeleted = 0;
+
+      // No need to cast ... this is pretty nifty,
+      // I find ... grab the elements as ReferencePlane
+      // instances, since the filter guarantees that 
+      // only ReferencePlane instances are selected.
+      // In Revit 2014, this attempt to delete the 
+      // reference planes while iterating over the 
+      // filtered element collector throws an exception:
+      // Autodesk.Revit.Exceptions.InvalidOperationException:
+      // HResult=-2146233088
+      // Message=The iterator cannot proceed due to 
+      // changes made to the Element table in Revit's 
+      // database (typically, This can be the result 
+      // of an Element deletion).
+      //
+      //foreach( ReferencePlane rp in col )
+      //{
+      //  ++n;
+      //  nDeleted += DeleteIfNotHosting( rp ) ? 1 : 0;
+      //}
+
+      ICollection<ElementId> ids = col.ToElementIds();
+
+      n = ids.Count();
+
+      if( 0 < n )
+      {
+        using( Transaction tx = new Transaction( doc ) )
+        {
+          tx.Start( string.Format(
+            "Delete {0} ReferencePlane{1}",
+            n, Util.PluralSuffix( n ) ) );
+
+          // This also causes the exception "One or more of 
+          // the elementIds cannot be deleted. Parameter 
+          // name: elementIds
+          //
+          //ICollection<ElementId> ids2 = doc.Delete(
+          //  ids );
+          //nDeleted = ids2.Count();
+
+          List<ElementId> ids2 = new List<ElementId>(
+            ids );
+
+          foreach( ElementId id in ids2 )
+          {
+            try
+            {
+              ICollection<ElementId> ids3 = doc.Delete(
+                id );
+
+              nDeleted += ids3.Count;
+            }
+            catch( Autodesk.Revit.Exceptions.ArgumentException )
+            {
+            }
+          }
+
+          tx.Commit();
+        }
+      }
+
+      Util.InfoMsg( string.Format(
+        "{0} unnamed reference plane{1} examined, "
+        + "{2} element{3} in total were deleted.",
+        n, Util.PluralSuffix( n ),
+        nDeleted, Util.PluralSuffix( nDeleted ) ) );
+
+      return Result.Succeeded;
+    }
+  }
+}