axTOCControl右键

private void axTOCControl1_OnMouseDown(object sender, ITOCControlEvents_OnMouseDownEvent e)
{
if (e.button != 2) return;

esriTOCControlItem item = esriTOCControlItem.esriTOCControlItemNone;
IBasicMap map = null; ILayer layer = null;
object other = null; object index = null;

//Determine what kind of item is selected
m_tocControl.HitTest(e.x, e.y, ref item, ref map, ref layer, ref other, ref index);

//Ensure the item gets selected
if (item == esriTOCControlItem.esriTOCControlItemMap)
m_tocControl.SelectItem(map, null);
else
m_tocControl.SelectItem(layer, null);

//Set the layer into the CustomProperty (this is used by the custom layer commands)
m_mapControl.CustomProperty = layer;

//Popup the correct context menu
if (item == esriTOCControlItem.esriTOCControlItemMap) m_menuMap.PopupMenu(e.x, e.y, m_tocControl.hWnd);
if (item == esriTOCControlItem.esriTOCControlItemLayer) m_menuLayer.PopupMenu(e.x, e.y, m_tocControl.hWnd);

}