New Post: How to select lots of features and display them really fast ?

I need to select lots of features in a polygon layer (about 500 of 2000 features in a shapefile). I select them by index and it works, but it took around 1 minutes to display the selection. How can I speed this up ?

layer = map1.AddLayer(@"C:\Users\royeral\Desktop\becancour\physitel\uhrh.shp") as DotSpatial.Controls.MapPolygonLayer;

...

// this simple loop take about 1 minutes 
for (int index = 0; index < 500; ++index)
    layer.Select(index);