//只用前五行，可以直接将选中的面要素的颜色全部修改成红色，也就是填充颜色            IRgbColor pRgbColor= new RgbColor();;            pRgbColor.Red = 255;            pRgbColor.Green = 0;            pRgbColor.Blue = 0;            IFeatureSelection pFtSelection = pFeatureLayer as IFeatureSelection;            //符号边线颜色 ，下边这五行设定选中面的边线，但是需要配合后边的代码执行            IRgbColor pLineColor = new RgbColor();            pLineColor.Red = 255;            ILineSymbol ilSymbl = new SimpleLineSymbolClass();            ilSymbl.Color = pLineColor;            ilSymbl.Width = 3;            //定义选中要素的符号为红色，这部分的作用并没有搞清楚，随后可能还需要研究             ISimpleFillSymbol ipSimpleFillSymbol = new SimpleFillSymbol();            ipSimpleFillSymbol.Outline = ilSymbl;            RgbColor pFillColor = new RgbColor();            pFillColor.Green = 60;            ipSimpleFillSymbol.Color = pFillColor;            ipSimpleFillSymbol.Style = esriSimpleFillStyle.esriSFSNull;//设置成填充效果为空，也就是不填充，有很多填充效果，这是个枚举            //ipSimpleFillSymbol.Style = esriSimpleFillStyle.esriSFSForwardDiagonal;            //选取要素集 ，这里需要把pFeatureLayer 转换成IFeatureSelection             IFeatureSelection pFtSelection = pFeatureLayer as IFeatureSelection;            pFtSelection.SetSelectionSymbol = true;            pFtSelection.SelectionSymbol = (ISymbol)ipSimpleFillSymbol;