public async Task DeleteCourseWithInstances(CourseInstanceUpdate instance)
        {
            ValidationErrors = null;
            try
            {
                await _courseService.DeleteWithInstances(instance.Course.Id);

                CourseInstances.RequestRefresh();
            }
            catch (ValidationException ve)
            {
                ValidationErrors = ve.Errors;
            }
        }
        public async Task DeleteCourse(CourseInstanceUpdate instance)
        {
            ValidationErrors = null;
            try
            {
                await _courseService.Delete(instance.Course.Id);

                //CourseInstances.RowEditOptions.EditRowId = null;
                CourseInstances.RequestRefresh();
            }
            catch (ValidationException ve)
            {
                ValidationErrors = ve.Errors;
            }
        }