将本地列表与EF Core中的Any子句一起使用时，表达式无法转换错误

Question

我有一个DateTime对象列表(本地列表(，我想在EF核心的查询中使用它，如下所示：

var teacher = _appDataContext
.Teachers
.AsExpandable()
.Where(x => x.Id.Equals(booking.Teacher.Id))
.Select(x => new
{
IsConflicted = x
.Bookings
.Any(y => booking.StartingTimes.Any(z => y.StartingTime <= z && z < y.EndingTime)) // booking.StartingTimes is a local list.
})
.FirstOrDefault();

但每当我运行代码时，它都会给我以下错误：

System.InvalidOperationException: The LINQ expression 'DbSet<Booking>
.Where(b0 => EF.Property<Nullable<Guid>>((EntityShaperExpression: 
EntityType: Teacher
ValueBufferExpression: 
(ProjectionBindingExpression: Outer.Outer)
IsNullable: False
), "Id") != null && EF.Property<Nullable<Guid>>((EntityShaperExpression: 
EntityType: Teacher
ValueBufferExpression: 
(ProjectionBindingExpression: Outer.Outer)
IsNullable: False
), "Id") == EF.Property<Nullable<Guid>>(b0, "TeacherId"))
.Any(b0 => __booking_StartingTimes_4
.Any(z => b0.StartingTime <= z && z < b0.EndingTime))' could not be translated. Either rewrite the query in a form that can be translated, or switch to client evaluation explicitly by inserting a call to either AsEnumerable(), AsAsyncEnumerable(), ToList(), or ToListAsync(). See https://go.microsoft.com/fwlink/?linkid=2101038 for more information.

这是否意味着我不能在本地列表中进行这种比较？还有其他方法可以实现我想要做的事情吗？

Answer 1

所以我能够解决这个问题。然而，我的解决方案需要添加LinqKit包：

首先，我通过在本地StartingTimes上循环来逐步构建一个谓词，如下所示：

Expression<Func<Booking, bool>> predicate = x => false;
booking.StartingTimes.ToList().ForEach(x => { predicate = predicate.Or(y => y.StartingTime <= x && x < y.EndingTime); });

之后，我只是使用谓词作为Any方法的参数，如下所示：

var teacher = _appDataContext
.Teachers
.AsExpandable()
.Where(x => x.Id.Equals(booking.Teacher.Id))
.Select(x => new
{
IsConflicted = x
.Bookings
.Any(predicate.Invoke())
})
.FirstOrDefault();