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值对象在ASP.NET Core 2.1中为无效对象

value-objects asp.net-core-2.1 entity-framework-core c#

2

Rashik · 技术社区 · 6 年前

我在ASP.NET Core2.0项目中使用了Value对象,该项目运行正常。

我将项目更新为2.1,它给了我一个错误,因为

Invalid object name 'EntityAdress'.

实体:

public class Company : AuditableEntity<long>
{
    public int SalesRepId { get; set; }
    public string Name { get; set; }
    public int StatusId { get; set; }
    public EntityAdress Addresses { get; set; }
    public string BillingAddress { get; set; }
}

public class EntityAdress : ValueObject
{
    private EntityAdress() { }
    public string Address { get; set; }
    public string City { get; set; }
    public string State { get; set; }
    public int Zip { get; set; }

    protected override IEnumerable<object> GetAtomicValues()
    {
        yield return Address;
        yield return City;
        yield return State;
        yield return Zip;
    }
}

ValueObject的实现与 Link for the eshopContainer examples of value objects

我用于包含 DbContext

<Project Sdk="Microsoft.NET.Sdk">


  <PropertyGroup>
    <TargetFramework>netcoreapp2.1</TargetFramework>
    <RuntimeFrameworkVersion>2.1.6</RuntimeFrameworkVersion>
  </PropertyGroup>


  <ItemGroup>
    <PackageReference Include="IdentityServer4.AspNetIdentity" Version="1.0.1" />
    <PackageReference Include="IdentityServer4.EntityFramework" Version="2.1.1" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="2.1.0" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="2.1.0" />
    <PackageReference Include="Microsoft.Extensions.Logging" Version="2.1.0" />
    <PackageReference Include="Microsoft.Extensions.Configuration.FileExtensions" Version="2.1.0" />
    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="2.1.0" />
  </ItemGroup>
</Project>

语境:

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.RemovePluralizingTableNameConvention();
    modelBuilder.OnDeleteCascading();

    modelBuilder.ApplyConfiguration(new CompanyEntityTypeConfiguraton());

    base.OnModelCreating(modelBuilder);

}

公司实体类型配置:

public class CompanyEntityTypeConfiguraton : IEntityTypeConfiguration<Company>
{
    public void Configure(EntityTypeBuilder<Company> orderConfiguration)
    {
        orderConfiguration.OwnsOne(p => p.Addresses, cb =>
        {
            cb.Property(p => p.City).HasColumnName("City");
            cb.Property(p => p.Address).HasColumnName("Address");
            cb.Property(p => p.State).HasColumnName("State");
            cb.Property(p => p.Zip).HasColumnName("Zip");
        });

    }
}

OnDelete级联和Remove复数表格名称约定:

public static class ModelBuilderExtensions
{
    public static void RemovePluralizingTableNameConvention(this ModelBuilder modelBuilder)
    {
        foreach (IMutableEntityType entity in modelBuilder.Model.GetEntityTypes())
        {
            entity.Relational().TableName = entity.DisplayName();
        }
    }
    public static void OnDeleteCascading(this ModelBuilder modelBuilder)
    {
        foreach (var relationship in modelBuilder.Model.GetEntityTypes().SelectMany(e => e.GetForeignKeys()))
        {
            relationship.DeleteBehavior = DeleteBehavior.Restrict;
        }
    }

}

问题的原因是什么?这是实体框架版本的问题还是实现中缺少的问题?

1 回复 | 直到 6 年前

1

3

Ivan Stoev 6 年前

在EF核心版本之间的实现中总是有一些变化。有些可能是错误修复,这会导致旧代码运行方式不同。

问题在于此代码:

public static void RemovePluralizingTableNameConvention(this ModelBuilder modelBuilder)
{
    foreach (IMutableEntityType entity in modelBuilder.Model.GetEntityTypes())
    {
        entity.Relational().TableName = entity.DisplayName();
    }
}

首先,您应该排除拥有的类型(记住拥有的类型仍然是ef core中的实体,因此包含在 GetEntityTypes() ):

modelBuilder.Model.GetEntityTypes().Where(t => !t.IsOwned())

否则,您将更改不为所属实体(所谓的表拆分)创建单独表的EF核心默认行为,以实际创建单独的表,因此,当EF核心构建连接到不存在的表的SQL查询时,您将得到异常。

第二,你应该叫那个代码之后所有Fluent配置,因为在开始时拥有的实体(如果没有标记 [Owned] 属性)尚未标识为这样的-它仅在 OwnsOne 电话。

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.ApplyConfiguration(new CompanyEntityTypeConfiguraton());

    base.OnModelCreating(modelBuilder);

    modelBuilder.RemovePluralizingTableNameConvention();
    modelBuilder.OnDeleteCascading();
}