I was selecting features using IFeatureSelection interface like as below.
IFeatureLayer2 featLayer = layer as IFeatureLayer2; IFeatureSelection featureSelection = featLayer as IFeatureSelection; featureSelection.SelectFeatures(spatialFilter, ESRI.ArcGIS.Carto.esriSelectionResultEnum.esriSelectionResultNew, false);
I selected all the features in the map as I used the spatial filter to the full map extent. But what I did not come across there are various enum options like esriSelectionResultEnum.esriSelectionResultAdd. I was thinking that this add narrows down the search more like it would filter out more records as like this.
//IQueryFilter2 qFilter = new QueryFilterClass(); //qFilter.WhereClause = "WORKORDERID != null"; //featureSelection.SelectFeatures(qFilter, ESRI.ArcGIS.Carto.esriSelectionResultEnum.esriSelectionResultAdd, false);
This immediate above snippet did not work for me But I am not very sure and I did not find much document on what scenario these options work and it would be great if it can be explained with snippet.