//===============图层添加字段
            polygonFeatureSet = (FeatureSet)mapMain.Layers[0].DataSet;
            polygonFeatureSet.Projection = mapMain.Projection;
            polygonFeatureSet.FeatureType = FeatureType.Polygon;
            DataColumn column = new DataColumn("IDxx", typeof(int));
            if (!polygonFeatureSet.DataTable.Columns.Contains("IDxx"))
            {
                  polygonFeatureSet.DataTable.Columns.Add(column);
            }
            polygonFeatureSet.Save();
//==============图层删除字段
            if (mapMain.Layers.Count > 0)
            {
                  MapPolygonLayer polygonLayer = default(MapPolygonLayer);
                  polygonLayer = (MapPolygonLayer)mapMain.Layers[0];
                  if (polygonLayer == null)
                  {
                        MessageBox.Show("The layer is not a polygon layer.");
                  }
                  else
                  {
                        polygonLayer.DataSet.DataTable.Columns.Remove("IDxx");
                        polygonLayer.DataSet.Save();
                        dataGridView1.DataSource = polygonLayer.DataSet.DataTable;
                  }
            }
            else
            {
                  MessageBox.Show("Please add a layer to the map.");
            }
原文:https://www.cnblogs.com/kogame/p/12268786.html