c# - 如何在 c# 中使用 PostgreSQL 在Sharpmap 上显示标签？

Question

 VectorLayer v = new VectorLayer("Point", new PostGIS("server=localhost;port=5433;user=postgres;pwd=9839757437;database=OSM3", "GhanaRegions", "Geometry", "id"));
 VectorLayer v1 = new VectorLayer("Point", new PostGIS("server=localhost;port=5433;user=postgres;pwd=9839757437;database=OSM3", "ghanalocation", "geometry", "id"));
 v.Style.EnableOutline = true;
 v.Style.Outline = Pens.Black;
 v.Style.Fill = Brushes.Red;
 v1.Style.PointColor = Brushes.White;
 SharpMap.Layers.LabelLayer layLabel = new SharpMap.Layers.LabelLayer("Name");
 layLabel.DataSource = new PostGIS("server=localhost;port=5433;user=postgres;pwd=9839757437;database=OSM3", "citie33", "geometry", "id");
 layLabel.Enabled = true;
 layLabel.LabelColumn = "Name";
 layLabel.MaxVisible = 2;
 layLabel.MaxVisible = 190;
 layLabel.MinVisible = 130;
 layLabel.MultipartGeometryBehaviour = SharpMap.Layers.LabelLayer.MultipartGeometryBehaviourEnum.Largest;
 layLabel.LabelFilter = SharpMap.Rendering.LabelCollisionDetection.ThoroughCollisionDetection;
 layLabel.PriorityColumn = "id";
 layLabel.Style.ForeColor = Color.Beige;
 layLabel.Style.Font = new Font(FontFamily.GenericSerif, 12);
 layLabel.Style.BackColor = new System.Drawing.SolidBrush(Color.FromArgb(128, 255, 0, 0));
 layLabel.Style.HorizontalAlignment = SharpMap.Styles.LabelStyle.HorizontalAlignmentEnum.Center;
 // map.Layers.Add(v1);
 map.Layers.Add(v);
 layLabel.Style.CollisionDetection = true;
 map.ZoomToExtents();
 pictureBox1.Image = map.GetMap();