实体框架核心 - 在列表中包含嵌套列表 [重复]

Question

如何在 Entity Framework Core 2.0.1 查询中包含另一个列表中的内部列表？

这是我尝试但没有成功的方法：

clase = repClase.ListQueryable(
    //Specification
    new ApplicationCore.Specifications.ClaseFilterByIdAndIdArticuloWithIncludesSpecification(idClase, idArticuloParam)
)
.Include(c => c.ReferenciasConstructor)
.ThenInclude(rc => rc.Select(rc1 => rc1.ReferenciaFabricanteTieneReferenciaConstructor))
.FirstOrDefault();

以及它抛出的错误： "属性表达式 'rc => {from ReferenciaConstructor rc1 in rc select [rc1].ReferenciaFabricanteTieneReferenciaConstructor}' 无效。该表达式应表示属性访问：'t => t.MyProperty'。 ”。

类：

[Table("Clases", Schema = "public")]
public class Clase
{

    ...

    [InverseProperty("Clase")]
    public IList<ReferenciaConstructor> ReferenciasConstructor { get; set; }

}

[Table("ReferenciasConstructor", Schema = "public")]
public class ReferenciaConstructor
{

    [Key]
    public int Id { get; set; }

    ...

    //JOIN TABLE
    [InverseProperty("ReferenciaConstructor")]
    public IList<ReferenciaFabricanteTieneReferenciaConstructor> ReferenciaFabricanteTieneReferenciaConstructor { get; set; }

}


//JOIN TABLE
[Table("ReferenciaFabricanteTieneReferenciaConstructor", Schema = "public")]
public class ReferenciaFabricanteTieneReferenciaConstructor {

    [Key]
    public int IdReferenciaFabricante { get; set; }

    [ForeignKey("IdReferenciaFabricante")]
    public ReferenciaFabricante ReferenciaFabricante { get; set; }

    [Key]
    public int IdReferenciaConstructor { get; set; }

    [ForeignKey("IdReferenciaConstructor")]
    public ReferenciaConstructor ReferenciaConstructor { get; set; }
}

Answer 1

您不能使用Include 来选择用途。只需select 所需的属性。

clase = repClase.ListQueryable(
        //Specification
        new ApplicationCore.Specifications.ClaseFilterByIdAndIdArticuloWithIncludesSpecification(idClase, idArticuloParam)
    )
    .Include(c => c.ReferenciasConstructor)
    .SelectMany(rc => rc.ReferenciasConstructor.Select(rc1 => rc1.ReferenciaFabricanteTieneReferenciaConstructor))
    .FirstOrDefault();