revit-api-code

Generate Revit API Code

Generate Revit API code for:

"$ARGUMENTS"

Clarify the target

Before writing code, confirm:

1. C# or Python?
   • C# → Revit macro (internal, .cs file in Revit's SharpDevelop IDE) or add-in (.dll)
   • Python → pyRevit script (.py file in a pyRevit extension bundle)
2. Where will it run?
   • Macro: runs from Manage → Macros, no installation needed
   • External command: compiled .dll, registered in .addin file
   • pyRevit: drop into extension folder, appears as ribbon button automatically
3. Revit version? Affects API availability.

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C# External Command (Add-in)

Complete, production-ready boilerplate for an IExternalCommand:

using System;
using System.Collections.Generic;
using System.Linq;
using Autodesk.Revit.Attributes;
using Autodesk.Revit.DB;
using Autodesk.Revit.UI;

namespace RevitBIMPlugin
{
    [Transaction(TransactionMode.Manual)]
    [Regeneration(RegenerationOption.Manual)]
    public class MyCommand : IExternalCommand
    {
        public Result Execute(
            ExternalCommandData commandData,
            ref string message,
            ElementSet elements)
        {
            UIApplication uiapp = commandData.Application;
            UIDocument    uidoc = uiapp.ActiveUIDocument;
            Document      doc   = uidoc.Document;

            try
            {
                using (Transaction tx = new Transaction(doc, "My BIM Operation"))
                {
                    tx.Start();

                    // ── Your code here ────────────────────────────────
                    // Example: count all walls
                    var walls = new FilteredElementCollector(doc)
                        .OfCategory(BuiltInCategory.OST_Walls)
                        .WhereElementIsNotElementType()
                        .ToElements();

                    tx.Commit();

                    TaskDialog.Show("BIM Manager",
                        $"Operation completed. Found {walls.Count} walls.");
                }

                return Result.Succeeded;
            }
            catch (Exception ex)
            {
                message = ex.Message;
                return Result.Failed;
            }
        }
    }
}