c# - EF延迟加载返回null

Question

我们在 EF 上遇到了问题。延迟加载时，有时导航属性返回 null。

注意:我在数据库上下文中创建了 this.Configuration.LazyLoadingEnabled = true;

型号:

public class Student
{
    public Int64 Id { get; set; }
    public string Name { get; set; }
    public string Gender { get; set; }

    public Int64 Address_Id { get; set; }

    [ForeignKey("Address_Id")]
    public virtual Address Address { get; set; }
}

public class Address
{
    public Int64 Id { get; set; }
    public string Name { get; set; }
}

数据库访问:

Student oStudnet = context.Students.FirstOrDefault();
Int64 addressId= oStudnet.Address.Id  

“oStudnet.Address.id”上的“空异常”//地址在这里为空

Answer 1

Student oStudnet = context.Students.Include("Address").FirstOrDefault();

然后就可以访问地址了