Update README.md

Author: SpeedCAD

README.md

@@ -16,3 +16,93 @@ With the ProgressMeter library, you can easily integrate a progress bar into the
 **Dark Theme**
 
 ![ProgressMeter](./rvt2024/progressmeterdark.gif)
+
+## Code example
+```c#
+using System.Collections.Generic;
+using Autodesk.Revit.Attributes;
+using Autodesk.Revit.DB;
+using Autodesk.Revit.UI;
+using SCADtools.Revit.UI;
+using System.Linq;
+using System;
+
+namespace SCADtools.ProgressMeterSample
+{
+    [TransactionAttribute(TransactionMode.Manual)]
+    internal class Sample : IExternalCommand
+    {
+        public Result Execute(ExternalCommandData commandData, ref string message, ElementSet elements)
+        {
+            UIApplication uiapp = commandData.Application;
+            UIDocument uidoc = uiapp.ActiveUIDocument;
+            Document doc = uidoc.Document;
+
+            //Initialize ProgressMeter
+            //By default the cancel button will be displayed
+            //If you don't want to show the cancel button, you must initialize it by passing false as an argument in the constructor
+            ProgressMeter progressMeter = new ProgressMeter();
+
+            try
+            {
+                List<Wall> walls = new FilteredElementCollector(doc)
+                                            .WhereElementIsNotElementType()
+                                                .OfClass(typeof(Wall))
+                                                    .Cast<Wall>()
+                                                        .ToList();
+
+                int count = walls.Count;
+
+                if (count > 0)
+                {
+                    //Set limit number
+                    progressMeter.SetLimit(count);
+
+                    //Initialize and make it visible (no display string)
+                    progressMeter.Start();
+
+                    using (Transaction tr = new Transaction(doc, "ProgressMeter - Updating Wall comments"))
+                    {
+                        tr.Start();
+
+                        int i = 1;
+
+                        foreach (Wall wall in walls)
+                        {
+                            //Set display string to be displayed to user
+                            //If the display string is static it can be assigned in the Start() method of the ProgressMeter class
+                            progressMeter.DisplayString = "Updating wall comments " + i.ToString() + " of " + count.ToString();
+
+                            //Increment Progress Meter
+                            progressMeter.MeterProgress();
+
+                            //Update comments
+                            Parameter parameter = wall.get_Parameter(BuiltInParameter.ALL_MODEL_INSTANCE_COMMENTS);
+                            parameter.Set("Comment " + i.ToString());
+
+                            //If the cancel button is pressed
+                            if (progressMeter.StopWorker) break;
+
+                            i++;
+                        }
+
+                        tr.Commit();
+                    }
+                }
+
+                return Result.Succeeded;
+            }
+            catch (Exception ex)
+            {
+                message = ex.Message;
+                return Result.Failed;
+            }
+            finally
+            {
+                //Stop and hide the ProgressMeter (IMPORTANT)
+                progressMeter.Stop();
+            }
+        }
+    }
+}
+```