BuildingCoder.CmdCreateSharedParams.GetCategory C# (CSharp) Метод

        Category GetCategory(
            Document doc,
            BuiltInCategory target)
        {
            Category cat = null;

              if ( target.Equals( BuiltInCategory.OST_IOSModelGroups ) )
              {
            // determine model group category:

            FilteredElementCollector collector
              = Util.GetElementsOfType( doc, typeof( Group ), // GroupType works as well
            BuiltInCategory.OST_IOSModelGroups );

            IList<Element> modelGroups = collector.ToElements();

            if ( 0 == modelGroups.Count )
            {
              Util.ErrorMsg( "Please insert a model group." );
              return cat;
            }
            else
            {
              cat = modelGroups[0].Category;
            }
              }
              else
              {
            try
            {
              cat = doc.Settings.Categories.get_Item( target );
            }
            catch ( Exception ex )
            {
              Util.ErrorMsg( string.Format(
            "Error obtaining document {0} category: {1}",
            target.ToString(), ex.Message ) );
              return cat;
            }
              }
              if ( null == cat )
              {
            Util.ErrorMsg( string.Format(
              "Unable to obtain the document {0} category.",
              target.ToString() ) );
              }
              return cat;
        }