Change the fill and outline color of features in an ArcGIS Server feature service with an ArcMap add-in

Summary

This code sample shows how to change the fill and outline color of features in an ArcGIS Server feature service using an ArcMap add-in. The changes can persist in ArcMap by saving the ArcMap document.

Procedure

 using System;
 using System.Collections.Generic;
 using System.Text;
 using System.IO;
 using ESRI.ArcGIS.esriSystem;
 using ESRI.ArcGIS.ArcMapUI;
 using ESRI.ArcGIS.Geodatabase;
 using ESRI.ArcGIS.Carto;
 using ESRI.ArcGIS.Geometry;
 using ESRI.ArcGIS.Display;

 namespace Add_FeatureService_to_ArcMap
 {
     public class Add_FeatureService_to_ArcMap : ESRI.ArcGIS.Desktop.AddIns.Button
     {
         public Add_FeatureService_to_ArcMap()
         {
         }

         protected override void OnClick()
         {
             IMxDocument pMx = ArcMap.Application.Document as IMxDocument;
             //You may replace this url with your own feature service url. In my case, I have an ArcGIS Server feature service that contains polygon features at the URL shown below:
             string url = "https://localhost:6080/arcgis/rest/services/FC1_Polygons/FeatureServer";
             IPropertySet pFeatServProp = new PropertySet();
             pFeatServProp.SetProperty("DATABASE", url);
             IWorkspaceFactory pFeatWorkspaceFact = new FeatureServiceWorkspaceFactory() as IWorkspaceFactory;
             IFeatureWorkspace pFeatureWorkspace = pFeatWorkspaceFact.Open(pFeatServProp, 0) as IFeatureWorkspace;
             IFeatureClass pfeatClass = pFeatureWorkspace.OpenFeatureClass("0") as IFeatureClass;
             // "0" corresponds to the first layer with index/id 0, similarly, "1", "2" refer to layer id 1
             // and id 2, you may check the service rest end point to have a valid parameter in the OpenFeatureClass.

             IFeatureLayer pfeatLayer = new FeatureLayer();
             pfeatLayer.FeatureClass = pfeatClass;
             pfeatLayer.Name = "Sami_FC1";
             IGroupLayer pGroupLayer = new GroupLayer();
             pGroupLayer.Name = "GroupLayerName";

             // -------------------------------- RENDERER ---------------------------------------------------  
             // Creating RGB Colors by pulling values from a Microsoft Color object
             System.Drawing.Color c = System.Drawing.Color.FromName("SlateBlue");
             IRgbColor rgbColor_Fill = CreateRgbColor(c);

             System.Drawing.Color c2 = System.Drawing.Color.FromName("Red");
             IRgbColor rgbColor_Outline = CreateRgbColor(c2);

             ISimpleLineSymbol simpleLineSymbol_Outline = new SimpleLineSymbol();
             simpleLineSymbol_Outline.Color = rgbColor_Outline;
             simpleLineSymbol_Outline.Width = 3.0;

             ISimpleFillSymbol simpleFillSymbol = new SimpleFillSymbol();
             simpleFillSymbol.Style = esriSimpleFillStyle.esriSFSSolid;
             simpleFillSymbol.Color = rgbColor_Fill;
             simpleFillSymbol.Outline = simpleLineSymbol_Outline;

             ISimpleRenderer simpleRenderer = new SimpleRenderer();
             simpleRenderer.Label = "Simple Renderer";
             simpleRenderer.Symbol = simpleFillSymbol as ISymbol;
             IFeatureRenderer featureRenderer = simpleRenderer as IFeatureRenderer;

             IGeoFeatureLayer geoFeatureLayer = pfeatLayer as IGeoFeatureLayer;
             geoFeatureLayer.Renderer = featureRenderer;

             //--------------------------------  END  RENDERER ---------------------------------------------------

             pGroupLayer.Add(pfeatLayer);
             pMx.FocusMap.AddLayer(pGroupLayer);

             ArcMap.Application.CurrentTool = null;
         }
         // Method used to extract RGB components out of the Microsoft Color object (a structure)
         protected static IRgbColor CreateRgbColor(System.Drawing.Color c)
         {
             // Note that c is a Microsoft color object, which has 4 components: alpha, R, G, B
             // The R, G, B components of the System.Drawing.Color object are assigned to the the ArcObjects IRgbColor object
             IRgbColor rgb = new RgbColorClass();
             rgb.Red = c.R; rgb.Green = c.G; rgb.Blue = c.B;
             rgb.UseWindowsDithering = false;
             return rgb;
         }
     }
}