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如何在IDesignTimeServices中正确使用IPluralizer

entity-framework-core asp.net-core c#

WueF · 技术社区 · 7 年前

在我的应用程序中,我使用代码优先的方法,只通过 IEntityTypeConfiguration<> 我的目标是实现多重表名,即。模型模型 .

读后 documentation , article , This question IPluralizer 在创建迁移期间使用,但不是。

DbSet<Model> Models {get;set;} 或使用 builder.ToTable("Models"); ,但在我的通用场景中,我希望避免这种情况,特别是我希望一些模型不要覆盖抽象的通用场景。

问题是,我是做错了什么,还是我误解了它的行为方式

public class AppDesignService : IDesignTimeServices
{
    public void ConfigureDesignTimeServices(IServiceCollection services)
    {
        Debugger.Launch();
        services.AddSingleton<IPluralizer, InflectorPluralizer>();
    }
}

MyDbContext.cs

public class AppDbContext : IdentityDbContext<AppUser,AppRole,Guid>
{
    public EmsDbContext(DbContextOptions options) : base(options)
    {
    }

    protected override void OnModelCreating(ModelBuilder builder)
    {
        base.OnModelCreating(builder);

        builder.ApplyConfigurationsFromAssembly(Assembly.GetAssembly(typeof(AppDbContext)));
    }
}

public void ConfigureServices(IServiceCollection services)
{
    var connectionString = Configuration.GetConnectionString("DefaultConnection");

    services.AddDbContext<DbContext, AppDbContext>(opt =>
     {
         opt.UseSqlServer(connectionString, sqlOpt =>
         {
             sqlOpt.EnableRetryOnFailure(3);
         });
     });

     // code skipped for brevity
}

配置

public interface IEntity
{
    int Id {get;set;}
}

public class Model : IEntity
{
    public int Id {get;set;}
    public string Name {get;set;}
}



public abstract class DbEntityConfig<T> : IEntityTypeConfiguration<T>
    where T : class, IEntity
{
    public void Configure(EntityTypeBuilder<T> builder)
    {
        builder.HasKey(m => m.Id);
    }
}


public class ModelEntityConfig : DbEntityConfig<Model>
{
    public void Configure(EntityTypeBuilder<Model> builder)
    {
        base.Configure(builder);

        // Of course I want to avoid this call, cos TheOtherModel might not override base method
        // builder.ToTable("Models");

        builder.Property(m => m.Name).HasMaxLength(25);
    }
}

结果

public partial class Test : Migration
{
    protected override void Up(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.CreateTable(
            name: "Model",
            columns: table => new

            // code skipped for brevity
    }
}

预期结果:

public partial class Test : Migration
{
    protected override void Up(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.CreateTable(
            name: "Models",
            columns: table => new

            // code skipped for brevity
    }
}

1 回复 | 直到 7 年前

Ivan Stoev 7 年前

Pluralization hook for DbContext Scaffolding EF核心文件:

EF Core 2.0引入了一种新的 IPluralizer DbSet

conventions

OnModelCreating . 大概是这样的:

foreach (var entityType in modelBuilder.Model.GetEntityTypes())
    entityType.Relational().TableName = GetTableName(entityType);

GetTableName 方法实现您的命名约定:

string GetTableName(IEntityType entityType)
{
    // use entiityType.Name and other info
    return ...; 
}

更新(EF Core 3.0+): 使用 entityType.SetTableName(...) entityType.Relational().TableName = ...