动态渲染面状图层：使用字段取值与颜色 Ramp

 public void PolyGonRender(IFeatureLayer pFLayer)
        {
            try
            {
                IGeoFeatureLayer pGeoLayer = (IGeoFeatureLayer)pFLayer;
                IClassBreaksRenderer pRender = new ClassBreaksRenderer();
                ESRI.ArcGIS.esriSystem.IClassifyGEN pClassifyGEN = new ESRI.ArcGIS.esriSystem.Quantile();
                ITableHistogram pTableHistogram = new ESRI.ArcGIS.CartoUI.TableHistogram() as ITableHistogram;
                ESRI.ArcGIS.CartoUI.IHistogram pHistogram = (ESRI.ArcGIS.CartoUI.IHistogram)pTableHistogram;
                pTableHistogram.Field = "数值";
                pTableHistogram.Table =(ITable) pFLayer.FeatureClass;

               object xVals,cb;
                object frqs;

                pHistogram.GetHistogram(out xVals,out frqs);

                int ss = 5;
                pClassifyGEN.Classify(xVals, frqs, ref ss);

                cb = pClassifyGEN.ClassBreaks;
                double[] breaks = (double[])cb;
                pRender = new ClassBreaksRenderer();
                pRender.Field = "数值";
                pRender.BreakCount = ss;
                pRender.MinimumBreak = breaks[0];


                IColor pFromColor = new RgbColor();
                pFromColor.RGB = Microsoft.VisualBasic.Information.RGB(0, 255, 0);