用於從MapControl中獲取可見圖層、獲取指定圖層名等：

using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using System.Collections.Generic;

namespace XXXX
{
    /// <summary>
    /// 圖層型別
    /// </summary>
    public enum EnumFeatureLayerType
    {
        /// <summary>
        /// 所有
        /// </summary>
        All,
        /// <summary>
        /// 點
        /// </summary>
        Point,
        /// <summary>
        /// 線
        /// </summary>
        Polyline,
        /// <summary>
        /// 面
        /// </summary>
        Polygon
    }

    /// <summary>
    /// 圖層工具類
    /// </summary>
    static class AELayerTool
    {
        /// <summary>
        /// 獲取可見要素圖層
        /// </summary>
        /// <param name="pMapControl">地圖控制元件</param>
        /// <param name="eFeatureLayerType">型別</param>
        /// <returns></returns>
        public static List<IFeatureLayer> GetVisableFeatureLayer(IMapControl2 pMapControl, EnumFeatureLayerType eFeatureLayerType = EnumFeatureLayerType.All)
        {
            List<IFeatureLayer> lstFeatureLayer = null;
            GetVisableFeatureLayer(pMapControl, ref lstFeatureLayer);
            if (null != lstFeatureLayer && 0 < lstFeatureLayer.Count && EnumFeatureLayerType.All != eFeatureLayerType)
            {
                esriGeometryType eGeometryType = esriGeometryType.esriGeometryNull;
                if (EnumFeatureLayerType.Point == eFeatureLayerType)
                {
                    eGeometryType = esriGeometryType.esriGeometryPoint;
                }
                else if (EnumFeatureLayerType.Polyline == eFeatureLayerType)
                {
                    eGeometryType = esriGeometryType.esriGeometryPolyline;
                }
                else if (EnumFeatureLayerType.Polygon == eFeatureLayerType)
                {
                    eGeometryType = esriGeometryType.esriGeometryPolygon;
                }
                var lstTempFeatureLayer = new List<IFeatureLayer>();
                foreach (var pFeatureLayer in lstFeatureLayer)
                {
                    if (esriFeatureType.esriFTSimple != pFeatureLayer.FeatureClass.FeatureType)
                        continue;
                    if (pFeatureLayer.FeatureClass.ShapeType != eGeometryType)
                        continue;
                    lstTempFeatureLayer.Add(pFeatureLayer);
                }
                lstFeatureLayer.Clear();
                if (0 < lstTempFeatureLayer.Count)
                {
                    lstFeatureLayer.AddRange(lstTempFeatureLayer);
                }
            }
            return lstFeatureLayer;
        }

        /// <summary>
        /// 獲取可見要素圖層
        /// </summary>
        /// <param name="pMapControl">地圖控制元件</param>
        /// <returns>要素圖層</returns>
        public static void GetVisableFeatureLayer(IMapControl2 pMapControl, ref List<IFeatureLayer> lstFeatureLayer)
        {
            if (null == lstFeatureLayer) lstFeatureLayer = new List<IFeatureLayer>();
            var layerCount = pMapControl.LayerCount;
            for (int i = 0; i < layerCount; i++)
            {
                var layer = pMapControl.Layer[i];
                GetVisableFeatureLayer(layer, ref lstFeatureLayer);
            }
        }

        public static void GetVisableFeatureLayer(ILayer pLayer, ref List<IFeatureLayer> lstFeatureLayer)
        {
            if (null == lstFeatureLayer) lstFeatureLayer = new List<IFeatureLayer>();
            if (pLayer is IFeatureLayer featureLayer)
            {
                if (featureLayer.Visible)
                    lstFeatureLayer.Add(featureLayer);
            }
            else
            {
                if (pLayer is ICompositeLayer compositeLayer)
                {
                    var nCount = compositeLayer.Count;
                    for (int i = 0; i < nCount; i++)
                    {
                        GetVisableFeatureLayer(compositeLayer.Layer[i], ref lstFeatureLayer);
                    }
                }
            }
        }

        public static string GetFeatureClassName(IFeatureLayer pFeatureLayer)
        {
            return GetFeatureClassName(pFeatureLayer.FeatureClass);
        }

        public static string GetFeatureClassName(IFeatureClass pFeatureClass)
        {
            return GetTableName(pFeatureClass);
        }

        public static string GetTableName(IFeatureClass pFeatureClass)
        {
            return GetTableName(pFeatureClass as ITable);
        }

        public static string GetTableName(ITable pTable)
        {
            var sUserFeatureClassName = (pTable as IDataset).Name;
            var nIndex = sUserFeatureClassName.IndexOf(".");
            if (nIndex > 0) sUserFeatureClassName = sUserFeatureClassName.Substring(nIndex + 1, sUserFeatureClassName.Length - nIndex - 1);
            return sUserFeatureClassName;
        }
    }
}