Question

关于如何在Entity Framework中禁用延迟加载的文章很多，但是相同的技术在EF Core中不起作用。我在变更跟踪器中找到了LazyLoadingEnabled属性，但这似乎根本不起作用。

一切都指向EF：

this.Configuration.LazyLoadingEnabled = false;

但是，EF Core中缺少Configuration属性。

以下是我所谈论的例子：

public class TestContext : DbContext
{
    public DbSet<Person> People { get; set; }
    public DbSet<Address> Addresses { get; set; }

    public TestContext()
    {
        this.ChangeTracker.LazyLoadingEnabled = false;
    }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {            
        var connection = new SqliteConnection($"Data Source=Test.db");
        connection.Open();

        var command = connection.CreateCommand();

        command.CommandText = $"PRAGMA foreign_keys = ON;";
        command.ExecuteNonQuery();

        optionsBuilder.UseSqlite(connection);
        optionsBuilder.UseLazyLoadingProxies(false);

        base.OnConfiguring(optionsBuilder);
    }

    private static void Main(string[] args)
    {
        Console.WriteLine("Hello World!");

        using (var context = new TestContext())
        {
            context.Database.EnsureCreated();

            var personKey = Guid.NewGuid().ToString();
            var addressKey = Guid.NewGuid().ToString();

            context.People.Add(new Entities.Person { PersonKey = personKey, BillingAddress = new Entities.Address { AddressKey = addressKey } });
            context.SaveChanges();
        }

        using (var context = new TestContext())
        {
            var people = context.People.ToList();

            foreach (var person in people)
            {
                if (person.BillingAddress == null) throw new Exception("The billing address wasn't loaded");
            }
        }
    }
}

以上内容引发了异常，因为即使我关闭了延迟加载，也没有加载BillingAddress。

我怀疑这是一个错误，但请告诉我不是。我在这里记录了它：https://github.com/aspnet/EntityFrameworkCore/issues/15802

您可以在此处下载示例： https://www.dropbox.com/s/mimvgvcmibr7em2/EFSQLiteTest.7z?dl=0

Answer 1

如果您的问题是禁用EF Core的LazyLoading，请尝试： this.ChangeTracker.LazyLoadingEnabled = false;

在实体框架核心中禁用延迟加载

1 个答案: