等级渲染

等级渲染

private void 等级图ToolStripMenuItem_Click(object sender, EventArgs e)
        {

            //获取当前图层 ，并把它设置成IGeoFeatureLayer的实例 
            IMap pMap = axMapControl1.Map;
            ILayer pLayer = pMap.get_Layer(0) as IFeatureLayer;
            IFeatureLayer pFeatureLayer = pLayer as IFeatureLayer;
            IGeoFeatureLayer pGeoFeatureLayer = pLayer as IGeoFeatureLayer;

            //获取图层上的feature
            IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;
            IFeatureCursor pFeatureCursor = pFeatureClass.Search(null, false);
            IFeature pFeature = pFeatureCursor.NextFeature();
            //

            //定义所需的接口对象和相关变量

            IClassBreaksUIProperties pUIProperties;
            object dataValues;
            object dataFrequency;
            //double[] cb;


            int breakIndex;
            long ClassesCount;
            int numClass;
            numClass = 10;
            double[] Classes;
            //
            /* We're going to retrieve frequency data from a population 
              field and then classify this data*/

            ITable pTable;
            pTable = pFeatureClass as ITable;
            IBasicHistogram pBasicHist = new BasicTableHistogram();
            ITableHistogram pTableHist;

            pTableHist = (ITableHistogram)pBasicHist;

            //Get values and frequencies for the population field into a table histogram object
            pTableHist.Field = "ID";
            pTableHist.Table = pTable;
            pBasicHist.GetHistogram(out dataValues, out dataFrequency);

            IClassifyGEN pClassifyGEN = new Quantile();
            pClassifyGEN.Classify(dataValues, dataFrequency, ref numClass);
            Classes = (double[])pClassifyGEN.ClassBreaks;
            ClassesCount = long.Parse(Classes.GetUpperBound(0).ToString());

            //Initialise a new class breaks renderer and supply the number of class breaks and the field to perform the class breaks on.
            IClassBreaksRenderer pClassBreaksRenderer = new ClassBreaksRenderer();
            pClassBreaksRenderer.Field = "ID";
            //pClassBreaksRenderer.BreakCount = ClassesCount;
            pClassBreaksRenderer.MinimumBreak = Classes[0];
            pClassBreaksRenderer.SortClassesAscending = true;
            //设置着色对象的分级数目
            pClassBreaksRenderer.BreakCount = int.Parse(ClassesCount.ToString());

            //创建并设置随机色谱
            IAlgorithmicColorRamp pColorRamp = new AlgorithmicColorRamp();
            pColorRamp.Algorithm = esriColorRampAlgorithm.esriCIELabAlgorithm;
            IEnumColors pEnumColors;
            IRgbColor pColor1 = new RgbColor();
            IRgbColor pColor2 = new RgbColor();
            pColor1.Red = 255;
            pColor1.Green = 210;
            pColor1.Blue = 210;
            pColor2.Red = 190;
            pColor2.Green = 0;
            pColor2.Blue = 170;
            pColorRamp.FromColor = pColor1;
            pColorRamp.ToColor = pColor2;
            pColorRamp.Size = numClass;
            bool ok = true;
            pColorRamp.CreateRamp(out ok);
            pEnumColors = pColorRamp.Colors;
            pEnumColors.Reset();// use this interface to set dialog properties 

            pUIProperties = pClassBreaksRenderer as IClassBreaksUIProperties;
            pUIProperties.ColorRamp = "Custom";

            ISimpleFillSymbol pSimpleMarkerSymbol = new SimpleFillSymbol();

            IColor pColor;
            int[] colors = new int[numClass];

            // be careful, indices are different for the diff lists    
            for (breakIndex = 0; breakIndex < ClassesCount; breakIndex++)
            {

                pClassBreaksRenderer.set_Label(breakIndex, Classes[breakIndex] + " - " + Classes[breakIndex + 1]);
                pUIProperties.set_LowBreak(breakIndex, Classes[breakIndex]);
                pSimpleMarkerSymbol = new SimpleFillSymbol();
                pColor = pEnumColors.Next();
                pSimpleMarkerSymbol.Color = pColor;
                colors[breakIndex] = pColor.RGB;

                pClassBreaksRenderer.set_Symbol(breakIndex, (ISymbol)pSimpleMarkerSymbol);
                pClassBreaksRenderer.set_Break(breakIndex, Classes[breakIndex + 1]);
            }

            //将等级图渲染对象与渲染图层挂钩
            pGeoFeatureLayer.Renderer = (IFeatureRenderer)pClassBreaksRenderer;
            //刷新地图和TOOCotrol
            IActiveView pActiveView = axMapControl1.Map as IActiveView;
            pActiveView.Refresh();
        }