Question

我有实体，服务和视图模型。我在服务中使用服务模型，并在从实体到服务模型的服务中使用服务模型，并返回IQueryable<UserServiceModel>，并在控制器中使用服务，但是当我尝试实现结果并将其映射到视图时带有Select it throw异常的模型：

ArgumentException：类型为'System.Collections.Generic.List 1[TestDriveServiceModel]' cannot be used for parameter of type 'System.Collections.Generic.IEnumerable 1 [TestDriveServiceModel]）方法'System.Collections.Generic.IAsyncEnumerable 1[TestDriveServiceModel] ToList[TestDriveServiceModel](System.Collections.Generic.IEnumerable 1 [TestDriveServiceModel]'的表达式参数名称：arg0

// the service map from entities to service models and returns them
// userServiceModels is the result of the service
// Here the error is thrown
var viewModel = await userServiceModels.Select(usm => new UserViewModel()
{
    TestDrivesCount = usm.TestDrives.Count()
}).ToListAsync();

public class UserServiceModel : IdentityUser
    {
        public string FirstName { get; set; }

        public string LastName { get; set; }

        public ICollection<TestDriveServiceModel> TestDrives { get; set; } = new List<TestDriveServiceModel>();
    }

public class TestDriveServiceModel
    {
        public string Id { get; set; }

        public string CarId { get; set; }
        public CarServiceModel Car { get; set; }

        public string UserId { get; set; }
        public UserServiceModel User { get; set; }

        public string StatusId { get; set; }
        public StatusServiceModel Status { get; set; }

        public DateTime ScheduleDate { get; set; }

        public string Comment { get; set; }
    }

public class User : IdentityUserEntity
    {
        public string FirstName { get; set; }

        public string LastName { get; set; }

        public ICollection<TestDriveEntity> TestDrives { get; set; } = new List<TestDriveEntity>();
    }

public class TestDriveEntity
    {
        public string Id { get; set; }

        [Required]
        public string CarId { get; set; }
        public BaseCarEntity Car { get; set; }

        [Required]
        public string UserId { get; set; }
        public User UserEntity { get; set; }

        [Required]
        public string StatusId { get; set; }
        public Status StatusEntity { get; set; }

        [Required]
        public DateTime ScheduleDate { get; set; }

        public string Comment { get; set; }
    }

IAsyncEnumerable不能用于IEnumerable类型的参数

0 个答案: