Engine中可否通过代码实现将图层折叠？

IMap map = axMapControl1.Map; 

for (int j = 0; j < map.LayerCount; j++) 

{ 

ILayer layer = axMapControl1.get_Layer(j); 

ILegendInfo info = layer as ILegendInfo; 

for (int i = 0; i < info.LegendGroupCount; i++) 

{ 

ILegendGroup legendGroup = info.get_LegendGroup(i); 

legendGroup.Visible = false; 

} 

} 

axTOCControl1.Update();