public Row Row {get;}

private void HookRowChangedEvent()
{
  // subscribe to the RowChangedEvent
  Table table = MapView.Active.Map.GetLayersAsFlattenedList().OfType<FeatureLayer>().FirstOrDefault().GetTable();
  RowChangedEvent.Subscribe(OnRowChangedEvent, table);
}

private Guid _currentRowChangedGuid = Guid.Empty;
protected void OnRowChangedEvent(RowChangedEventArgs args)
{
  // RowEvent callbacks are always called on the QueuedTask so there is no need 
  // to wrap your code within a QueuedTask.Run lambda.

  var row = args.Row;

  // check for re-entry  (only if row.Store is called)
  if (_currentRowChangedGuid == args.Guid)
    return;

  var fldIdx = row.FindField("POLICE_DISTRICT");
  if (fldIdx != -1)
  {
    //Validate any change to �police district�
    //   cancel the edit if validation on the field fails
    if (row.HasValueChanged(fldIdx))
    {
      // cancel edit with invalid district (5)
      var value = row["POLICE_DISTRICT"].ToString();
      if (value == "5")
      {
        //Cancel edits with invalid �police district� values
        args.CancelEdit($"Police district {row["POLICE_DISTRICT"]} is invalid");
      }
    }

    // update the description field
    row["Description"] = "Row Changed";

    //  this update with cause another OnRowChanged event to occur
    //  keep track of the row guid to avoid recursion
    _currentRowChangedGuid = args.Guid;
    row.Store();
    _currentRowChangedGuid = Guid.Empty;
  }
}

private static FeatureLayer featureLayer;
private static void DetermineGeometryChange()
{
  featureLayer = MapView.Active?.Map.GetLayersAsFlattenedList().OfType<FeatureLayer>().FirstOrDefault();
  if (featureLayer == null)
    return;

  QueuedTask.Run(() =>
  {
    //Listen to the RowChangedEvent that occurs when a Row is changed.
    ArcGIS.Desktop.Editing.Events.RowChangedEvent.Subscribe(OnRowChangedEvent2, featureLayer.GetTable());
  });
}
private static void OnRowChangedEvent2(RowChangedEventArgs args)
{
  // RowEvent callbacks are always called on the QueuedTask so there is no need 
  // to wrap your code within a QueuedTask.Run lambda.

  //Get the layer's definition
  var lyrDefn = featureLayer.GetFeatureClass().GetDefinition();
  //Get the shape field of the feature class
  string shapeField = lyrDefn.GetShapeField();
  //Index of the shape field
  var shapeIndex = lyrDefn.FindField(shapeField);
  //Original geometry of the modified row
  var geomOrig = args.Row.GetOriginalValue(shapeIndex) as Geometry;
  //New geometry of the modified row
  var geomNew = args.Row[shapeIndex] as Geometry;
  //Compare the two
  bool shapeChanged = geomOrig.IsEqual(geomNew);
}