       //ָͼ
        public IFeatureLayer getLayer(string layername)
        {
            ILayer pLayer = null;
            IFeatureLayer pFeatureLayer = null;
            for (int i = 0; i < axMapControl1.LayerCount;i++ )
            {
                pLayer = axMapControl1.Map.get_Layer(i);
                if (pLayer.Name.ToLower() == layername)
                {
                    pFeatureLayer = pLayer as IFeatureLayer;
                    return pFeatureLayer;
                } 
            }
            return null;
        }