给定桩号获取纵断面中的高程值（c# for civil3d）

 1         /// <summary>
 2         /// 给定桩号值获取纵断面中的高程值，2018年4月21日
 3         /// 如果给定的桩号在纵断面范围内，则返回对应的高程值，否则返回null
 4         /// </summary>
 5         /// <param name="profile"></param>
 6         /// <param name="station"></param>
 7         /// <returns></returns>
 8         public static double? GetElevationFromProfile(this Profile profile, double station)
 9         {
10             double? elevation = null;//定义一个可空类型的数据
11             var startStation = profile.StartingStation;
12             var endStation = profile.EndingStation;
13             if (station >= startStation && station <= endStation)//判断桩号在纵断面桩号范围之内
14             {
15                 elevation = profile.ElevationAt(station);
16             }
17 
18             return elevation;
19         }

 1         [CommandMethod("getElvFromProfile")]
 2         public static void GetElvFromProfile()
 3         {
 4             Document doc = AcadApp.DocumentManager.MdiActiveDocument;
 5             Database db = doc.Database;
 6             Editor ed = doc.Editor;
 7             CivilDocument civilDoc = CivilApplication.ActiveDocument;
 8             var opt = new PromptEntityOptions("\n 请拾取一个纵断面对象 ");
 9             opt.SetRejectMessage("\n 对象必须是纵断面对象");
10             opt.AddAllowedClass(typeof(Profile), false);
11             var res = ed.GetEntity(opt);
12             if (res.Status != PromptStatus.OK)
13             {
14                 ed.WriteMessage("\n你已经取消了选择");
15                 return;
16             }
17             var doubleResult = ed.GetDouble("\n请输入一个桩号");
18             double station = doubleResult.Value;
20             using (DocumentLock docLock = doc.LockDocument())
21             using (Transaction trans = db.TransactionManager.StartTransaction())
22             {
23                 Profile profile = trans.GetObject(res.ObjectId, OpenMode.ForRead) as Profile;//获取纵断面对象
24                 double? elevation = profile.GetElevationFromProfile(station);//调用扩展方法，获取高程值
25                 //ed.WriteMessage(profile.GetElevationFromProfile(station).ToString());
26                 ed.WriteMessage(elevation?.ToString());
27             } 
28         }