Filtering for all instances, of all types, of a particular family.

[ppirtle]

[Disclaimer:C# and Revit API Newbie) Here's what I'm trying to do:

A. Iterate through all instances of the "Weld Symbol" family. (I want to iterate *all* types, which will include "Bottom," "Top," "Both," and "None")

B. (Assuming I've located the first instance) temporarily store the values for a number of the instance's parameters.

C. Replace the instance with the same type from the "Weld Symbol (MKA)" family. I want to do this programmatically, because if I do it by simply doing a "Select all instances" command, the parameter settings all get removed.

D. Set the now-reset parameters with the stored parameter values

E. Move on to the next instance.




From locating and trying many examples, below is the code I've gotten to work so far. Obviously, it only locates instances named "Top" from ANY family.

 
               string prompt;

                //Get the application
                UIApplication uiApp = commandData.Application;

                //Get the document
                Document doc = uiApp.ActiveUIDocument.Document;

                //Create a filtered element collector based on the document
                FilteredElementCollector collector = new FilteredElementCollector(doc);

                //Set the collector to look for a particular class
                collector = collector.OfClass(typeof(FamilySymbol));

                //var query = from element in collector where element.Name == "Bottom" select element;
                var query = from element in collector where element.Name == "Top" select element;

                //Create a list from the query
                List<Element> famSyms = query.ToList<Element>();

                //Get the element ID of the first family symbol
                ElementId symbolId = famSyms[0].Id;

                //Create a new filter to look for elements matching the element ID
                FamilyInstanceFilter filter = new FamilyInstanceFilter(doc, symbolId);

                //Reset the collector?????????????????
                collector = new FilteredElementCollector(doc);

                //Create an indexed collector of element type instances which pass the symbolId filter
                ICollection<Element> familyInstances = collector.WherePasses(filter).ToElements();

                //Report the number of family type instances found
                prompt = "Count = " + Convert.ToString(familyInstances.Count);
                TaskDialog.Show("Revit", prompt);

And, my questions are:

1. (Step A, above) How do I filter for all instances of a particular family?

2. Any suggestions how to proceed with Steps B, C, D, and E? (Please see disclaimer at the top of the post) LOL

3. In my code, what is the need for the step reading "collector = new FilteredElementCollector(doc);?"


Thanks, in advance, for your help and suggestions.

[ppirtle]

C'mon, now. I *know* this is an easy question for you skilled programmers out there. Can you help this newbie out a bit?