Revit二次开发之“PromptForFamilyInstancePlacement()函数动态拖动/鼠标跟随”效果

布置设备的时候，希望有个拖动的效果，这个函数可以实现。

//跟随鼠标拖动效果
[Transaction(TransactionMode.Manual)]
[Regeneration(RegenerationOption.Manual)]
public class DragElement : IExternalCommand
{
    public Result Execute(ExternalCommandData cmdData, ref string msg, ElementSet elements)
    {
        UIDocument uiDoc = cmdData.Application.ActiveUIDocument;

        FilteredElementCollector collector = new FilteredElementCollector(uiDoc.Document);
        IList<Element> collection = collector.OfClass(typeof(FamilySymbol)).OfCategory(BuiltInCategory.OST_DuctFitting).ToElements();

        FamilySymbol familySymbol = collection[0] as FamilySymbol;

        uiDoc.PromptForFamilyInstancePlacement(familySymbol);//重点。进入布置管件状态

        return Result.Succeeded;
    }
}

from:http://revit.5d6d.com/thread-1233-1-1.html