New Post: HOW TO check if a point is within or in a radius of a polygon?

// ...var trackedFids = new System.Collections.Generic.List<int>();

var candidates = sishp.QueryFeatures(new DotSpatial.Data.Extent(geom.Envelope));
foreach (var candidate in candidates)
{
    if (geom.Contains(DotSpatial.Topology.Geometry.FromBasicGeometry(candidate.BasicGeometry)))
    {
        trackedFids.Add(candiate.Fid);
        // do sth with candidate
    }
}
/*
 * A couple of lines  later....
 */
trackedFids.Sort();
int found = 0
foreach(var candidate in shp....Features)
{
    
    if (found < trackedFids.Count && trackedFids[found] == candiate.Fid)
    {
        while (trackedFids[found] == candiate.Fid)
                     //plus!  
            found = found + 1;
        continue;
    }
    // Do sth with candidate
}