使用AE加载带有制图表达（Representation）的图层（Layer）

制图表达（Representation）就是如下图的东西，一个能把样式保存到数据而不用依赖mxd的东东。

在ArcMap中添加这些有制图表达的图层，添加时就会自动加载制图表达作为样式。但在AE中，添加图层时制图表达不会自动使用，需要如下代码

1.先获取IRepresentationWorkspaceExtension接口

                IWorkspaceExtensionManager tWorkspaceExtManager = tWorkspace as IWorkspaceExtensionManager;
                UID tUID = new UIDClass();
                tUID.Value = "{FD05270A-8E0B-4823-9DEE-F149347C32B6}";
                IRepresentationWorkspaceExtension tRepWorkspaceExt = tWorkspaceExtManager.FindExtension(tUID) as IRepresentationWorkspaceExtension;

2.先用FeatureClassRepresentationNames获取FeatureClass对应的IRepresentationClass名称，然后再获取IRepresentationClass，最后实例化RepresentationRendererClass并赋值属性RepresentationClass，此时再把图层添加到MapControl中则带有制图表达。

                    IEnumDatasetName tEnumDatasetName = tRepWorkspaceExt.get_FeatureClassRepresentationNames(pFeatLayer.FeatureClass);
                    tEnumDatasetName.Reset();                 
                    IDatasetName tDatasetName = tEnumDatasetName.Next();
                    if (tDatasetName != null)
                    {
                       IRepresentationClass tRepClass = tRepWorkspaceExt.OpenRepresentationClass(tDatasetName.Name);

                        IRepresentationRenderer tRepresentationRenderer = new RepresentationRendererClass();
                        tRepresentationRenderer.RepresentationClass = tRepClass;

                        tGeoFeatLayer.Renderer = tRepresentationRenderer as IFeatureRenderer;

       　　            }

 总的思路就是，通过IRepresentationWorkspaceExtension获取该图层对应的IRepresentationClass，从而构成渲染对象IRepresentationRenderer