EF Core ThenInclude 外键值与 1:n relationshop

Question

我有一个 Transaction 有多个 TransactionLines。 transactionLine 有 SubCategory，SubCategory 有 Category.

我正在尝试获取交易列表。我希望能够列出交易及其分配的类别。通常一个 Transaction 有一个 TransactionLine，但也可以有多个，每个 Line 有不同的类别。

我正尝试在我的客户端 Linq 语句中执行此操作，但我的包含让我失望。

        var data = context.Transaction
            .Include(x => x.CreditAccount)
            .Include(x => x.DebitAccount)
            .Include(x => x.TransactionLines)
            .ThenInclude(x=>x.TransactionLines.SubCategory)
            .ThenInclude(x=>x.TransctionLines.SubCategory.Category)
            .Include(x => x.Budget)

ThenInclude 行不正确。它不提供 SubCategory。只有 Sum、First 等

我正在努力实现：

SELECT 
FROM Transaction t
INNER JOIN TransactionLine tl ON tl.TransactionId = t.Id
INNER JOIN SubCategory sc ON sc.Id = tl.SubCategoryId
INNER JOIN Category c ON c.Id = sc.CategoryId

但我似乎无法正确理解 SubCategory 部分。

我的 TransactionLine class 有一个 SubCategory 对象。

 public virtual Subcategory Subcategory { get; set; }

但是我好像无法访问这个。任何帮助都会很棒。

实体：

交易：

internal class Transaction 
    {
        [Key, Required, Column(Order = 1)]
        public int Id { get; set; }

        [Required, Column(Order = 2)]
        public Guid ExternalId { get; set; }

        [Required, Column(TypeName = "date", Order = 3)]
        public DateTime Date { get; set; }

        [Column(Order = 4)]
        public string Description { get; set; }

        [Required, Column(Order = 3), InverseProperty("TransactionDebitAccount")]
        public virtual Account DebitAccount { get; set; } // Nav

        [Required, Column(Order = 4), InverseProperty("TransactionCreditAccount")]
        public virtual Account CreditAccount { get; set; } // Nav

        [Required]
        public virtual List<TransactionLine> TransactionLines { get; set; } //Nav
    }

交易行

internal class TransactionLine
    {
        [Key, Required, Column(Order = 0)]
        public int Id { get; set; }

        [Required, Column(Order = 1)]
        public Guid ExternalId { get; set; }

        [Required, Column(Order = 2)]
        public virtual Transaction Transaction { get; set; } // Nav 

        [Column(Order = 5), Range(0.01, 999999.99, ErrorMessage = "Amount must be between 0.01 and 999,999.99")]
        public decimal Amount { get; set; }

        [Column(Order = 6)]
        public virtual Budget Budget { get; set; }

        [Column(Order = 7)]
        public virtual Subcategory Subcategory { get; set; }

    }

子类别

internal class Subcategory : EntityAudit
{
    [Required, Key]
    public int Id { get; set; }

    [Required]
    public Guid ExternalId { get; set; }

    [Required, StringLength(30, MinimumLength = 2, ErrorMessage = "Subcategory Name must be between 2 and 30 charactors")]
    public string Name { get; set; }

    [Required]
    public Category Category { get; set; }
}

Answer 1

尝试以下操作：

.ThenInclude(x=>x.Subcategory)
.ThenInclude(x=>x.Category)

ThenInclude() "works" 与先前选择的属性，在您的情况下，第一种情况是 TransactionLine，第二种情况是 Subcategory .

不要介意自动完成没有为您提供 TransactionLine/Subcategory 的正确属性。在这种情况下，我认为它会被 2 个 ThenInclude() 重载混淆。

EF Core ThenInclude 外键值与 1:n relationshop

EF Core ThenInclude foreign key values with 1:n relationshop

c#

entity-framework

linq

ef-core-2.2