SzmediTools/Szmedi.RvKits/MEPTools/FlipWorkplaneCmd.cs

using Autodesk.Revit.Attributes;
using Autodesk.Revit.DB;

using Nice3point.Revit.Toolkit.External;

using System;

using System.Linq;

namespace Szmedi.RvKits.MEPTools
{
    [Transaction(TransactionMode.Manual)]
    public class FlipWorkplaneCmd : ExternalCommand
    {
        public override void Execute()
        {
            ICollection<FamilyInstance> familyInstances;
            if (UiDocument.Selection.GetElementIds().Count > 0)
            {
                familyInstances = UiDocument.Selection.GetElementIds().Select(Document.GetElement).OfType<FamilyInstance>().ToList();

            }
            else
            {
                familyInstances = UiDocument.SelectObjects<FamilyInstance>("请选择族实例");
            }
            Document.Invoke(
                ts =>
                {
                    foreach (var ins in familyInstances)
                    {
                        if (ins.CanFlipWorkPlane)
                        {
                            ins.IsWorkPlaneFlipped = !ins.IsWorkPlaneFlipped;
                        }
                    }
                });
        }
    }
}