HiTeach API修正：stuLists無法取得對應

TEAMModelOS/Controllers/Client/HiTeachController.cs

@@ -263,8 +263,8 @@ namespace TEAMModelOS.Controllers.Client
                             examExtobj.period = obj.GetProperty("period");
                             examExtobj.grades = obj.GetProperty("grades");
                             examExtobj.subjects = obj.GetProperty("subjects");
-                            examExtobj.classes = obj.GetProperty("classes");
-                            examExtobj.stuLists = obj.GetProperty("stuLists");
+                            examExtobj.classes = (obj.TryGetProperty("classes", out JsonElement classes)) ? classes.ToObject<List<string>>() : new List<string>();
+                            examExtobj.stuLists = (obj.TryGetProperty("stuLists", out JsonElement stuLists)) ? stuLists.ToObject<List<string>>() : new List<string>();
                             examExtobj.finishClasses = (examClassFinDic.ContainsKey(examId)) ? examClassFinDic[examId] : new List<string>();
                             examExtobj.papers = obj.GetProperty("papers");
                             //examExtobj = obj.ToObject<object>();
@@ -552,8 +552,8 @@ namespace TEAMModelOS.Controllers.Client
                             examExtobj.period = obj.GetProperty("period");
                             examExtobj.grades = obj.GetProperty("grades");
                             examExtobj.subjects = obj.GetProperty("subjects");
-                            examExtobj.classes = obj.GetProperty("classes");
-                            examExtobj.stuLists = obj.GetProperty("stuLists");
+                            examExtobj.classes = (obj.TryGetProperty("classes", out JsonElement classes)) ? classes.ToObject<List<string>>() : new List<string>();
+                            examExtobj.stuLists = (obj.TryGetProperty("stuLists", out JsonElement stuLists)) ? stuLists.ToObject<List<string>>() : new List<string>();
                             examExtobj.finishClasses = (examClassFinDic.ContainsKey(examId)) ? examClassFinDic[examId] : new List<string>();
                             examExtobj.papers = obj.GetProperty("papers");
                             //examExtobj = obj.ToObject<object>();