c# - Entity Framework - 如何将测试数据播种到使用每类型表继承的实体？

Question

我正在使用 EF5 代码优先、迁移和每类型表继承。我有一些从其他类继承的类。例如，Tenant 和 Landlord 继承自 UserProfile。

我正在使用 protected override void Seed() 方法将测试数据添加到我的数据库中。例如，我创建 2 个 UserProfile 对象、1 个租户和 1 个房东。如何确保租户实体与第一个用户配置文件实体关联，而房东实体与第二个用户配置文件实体关联？因为我使用的是按类型表继承，所以我是否需要显式声明派生类的 UserId 等于其基类的 UserId ？我四处搜寻但找不到任何有用的东西。我尝试这样做:

protected override void Seed(Context context)
    {
        var users = new List<UserProfile>
        {
             new UserProfile { UserId=1, UserName="Matt", Email="<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="7e1f3e1f501d1113" rel="noreferrer noopener nofollow">[email protected]</a>", AccountType=AccountType.Tenant },
             new UserProfile { UserId=2, UserName="Dave", Email="<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="82e3c2e3ace1edef" rel="noreferrer noopener nofollow">[email protected]</a>", AccountType=AccountType.Landlord }
        };
        users.ForEach(u => context.UserProfile.AddOrUpdate(u));
        context.SaveChanges();

        var tenants = new List<Tenant>
        {
            new Tenant { UserId = users.Single(x => x.UserId = 1) /* other properties */  }
            // ...
        };
        tenants.ForEach(t => context.Tenant.AddOrUpdate(t));
        context.SaveChanges();

        var landlords = new List<Landlord>
        {
            new Landlord { UserId = users.Single(x => x.UserId = 2) /* other properties */ }
            // ...
        };
        landlords.ForEach(l => context.Tenant.AddOrUpdate(l));
        context.SaveChanges();
    }

Answer 1

您必须使用 DbContext 来加载要分配给它的实体。

这应该可以做到:

protected override void Seed(Context context)
    {
        var users = new List<UserProfile>
    {
         new UserProfile { UserId=1, UserName="Matt", Email="<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="117051703f727e7c" rel="noreferrer noopener nofollow">[email protected]</a>", AccountType=AccountType.Tenant },
         new UserProfile { UserId=2, UserName="Dave", Email="<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="dbba9bbaf5b8b4b6" rel="noreferrer noopener nofollow">[email protected]</a>", AccountType=AccountType.Landlord }
    };
        users.ForEach(u => context.UserProfile.AddOrUpdate(u));
        context.SaveChanges();

        var tenants = new List<Tenant>
    {
        new Tenant { UserId = users.Single(x => x.UserId = context.UserProfile.First(x=>x.UserId = 1)) /* other properties */  }
        // ...
    };
        tenants.ForEach(t => context.Tenant.AddOrUpdate(t));
        context.SaveChanges();

        var landlords = new List<Landlord>
    {
        new Landlord { UserId = users.Single(x => x.UserId = context.UserProfile.First(x=>x.UserId = 2)) /* other properties */ }
        // ...
    };
        landlords.ForEach(l => context.Tenant.AddOrUpdate(l));
        context.SaveChanges();
    }