public void LayersExamples()
 {
     // 获得captial、world、ocean数据集          
     Dataset dataset0 = datasource.Datasets["capital"];
     Dataset dataset1 = datasource.Datasets["world"];
     Dataset dataset2 = datasource.Datasets["ocean"];

     //获得图层集合
     Layers layers = mapControl1.Map.Layers;

     //构造矢量图层设置对象并设置其属性
     LayerSettingVector layerSettingVector = new LayerSettingVector();
     GeoStyle style = new GeoStyle();
     style.FillForeColor = Color.HotPink;
     layerSettingVector.Style = style;

     //对图层集合进行操作，包括删除、添加、插入、移动、清除等
     layers.Clear();

     layers.Add(dataset1, new LayerSettingVector(), true);
     layers.Add(dataset0, new LayerSettingVector(), true);
     MessageBox.Show(layers.Count + "");
     m_mapControl.Map.Refresh();

     layers.Insert(2, dataset2, new LayerSettingVector());
     MessageBox.Show(layers.Count + "");
     m_mapControl.Map.Refresh();

     layers.MoveDown(2);

     layers.Remove(2);
     MessageBox.Show(layers.Count + "");
     m_mapControl.Map.Refresh();

 }