C#+Arcgis Engine 唯一值渲染

        public static void Renderer(ILayer layer)
        {

            IFeatureLayer pFeatureLayer = layer as IFeatureLayer;
            IGeoFeatureLayer pGeoFeatureLayer = layer as IGeoFeatureLayer;
 
 
            //获取图层上的feature
            IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;
 
            IFeatureCursor pFeatureCursor = pFeatureClass.Search(null, false);
 
            //定义单值图渲染组件   
            IUniqueValueRenderer pUniqueValueRenderer = new UniqueValueRendererClass();
            //设置渲染字段对象        
            pUniqueValueRenderer.Fi