c# - 错误：sequence contains no element 最近我们升级到 .NetFramework 4.7.2 t 4.8 版本

Question

我有如下枚举

public enum CarTypes
 {
    Minicooper= 0,
    ferrari= 1,
    Benz= 2,
    Audi= 4,        
 } 

public ObservableCollection<CarTypes> availableCarList 

public ObservableCollection<CarTypes> AvailableCarList{
 get{
    List<CarTypes> availableList = Enum.GetValues(typeof(CarTypes))
                    .Cast<CarTypes>()
                    .Where(item =>
                            item == CarTypes.Minicooper ||
                        item == CarTypes.ferrari ||
                            item == CarTypes.Benz ||
                            item == CarTypes.Audi)
                    .ToList();

     availableCarList = new ObservableCollection<CarTypes> 
                                     (availableList);
     return availableCarList;  
   }
 }
public void updatecarslist()
{
    var carList = 
        Enum.GetValues(typeof(CarTypes)).Cast<availableCarList> 
        ().ToList();

    //which retrives which car's sold same enumtypes only
    var removedOnes = availableCarList.Except(carList).Tolist();
    foreach (var item in removedOnes)
            {
                if (availableCarList .Count > 0)                   
                availableCarList.Remove(item);
            }
        }
  }

previously it works as expected after upgrading 4.8 it giving. Please 

让我知道是否有人有任何想法。提前感谢您的帮助

当我们尝试从列表中删除枚举项时，问题就来了，就像序列不包含任何元素但该元素正在从可观察集合中删除

标签： c#collectionsenums