Revit二次开发之“先设置族类型再调用命令”

假如你要画一个风管，默认进画矩形风管，假如你希望画你已经选定的风管，比如圆形

[Transaction(TransactionMode.Manual)]
[Regeneration(RegenerationOption.Manual)]
//[Journaling(JournalingMode.NoCommandData)]
public class SetDefaultFamilySymbol : IExternalCommand
{
    public Result Execute(ExternalCommandData commandData, ref string message, ElementSet elements)
    {
        UIDocument uiDoc = commandData.Application.ActiveUIDocument;
        Autodesk.Revit.ApplicationServices.Application app = commandData.Application.Application;

        Transaction ts = new Transaction(uiDoc.Document, "test");
        ts.Start();

        HyRevit.Key.Press.Keys("DT");//调用Revit画风管的命令

        FilteredElementCollector collector = new FilteredElementCollector(uiDoc.Document);
        collector.OfClass(typeof(DuctType)).OfCategory(BuiltInCategory.OST_DuctCurves);

        IList<Element> list = collector.ToElements();
        FamilySymbol fi = null;
        foreach (Element el in list)
        {
            if (el.Name == "Tees")
                fi = el as FamilySymbol;
        }
        if (fi != null)
            uiDoc.PromptForFamilyInstancePlacement(fi);

        ts.Commit();

        return Autodesk.Revit.UI.Result.Succeeded;
    }
}

from:http://revit.5d6d.com/thread-914-1-4.html