在使用基于约定的导航时，我们可能会遇到一些问题。例如，在使用单向导航时，你不能访问导航到的实体的导航属性，因为它们未加载。同样，在使用双向导航时，你需要添加额外的逻辑来确保双向导航正确。

下面是一些示例代码，展示如何解决这些问题：

使用单向导航

public class Order
{
    public int OrderId { get; set; }
    public int CustomerId { get; set; }
    public Customer Customer { get; set; }
}

public class Customer
{
    public int CustomerId { get; set; }
    public string Name { get; set; }
}

// To access the Customer's orders, you need to explicitly include them
var customer = context.Customers
                .Include(c => c.Orders)
                .FirstOrDefault(c => c.CustomerId == 1);

// Alternatively, you can fetch the orders directly and then get the customer
var order = context.Orders
            .Include(o => o.Customer)
            .FirstOrDefault(o => o.OrderId == 1);

var customer = order.Customer;

使用双向导航

public class Order
{
    public int OrderId { get; set; }
    public int CustomerId { get; set; }
    public Customer Customer { get; set; }
}

public class Customer
{
    public int CustomerId { get; set; }
    public string Name { get; set; }
    public ICollection Orders { get; set; }
}

// Adding an order to a customer's orders should automatically set the customer
var customer = context.Customers.Find(1);
var newOrder = new Order { Customer = customer };
customer.Orders.Add(newOrder);

// Removing an order from a customer's orders should also update the order's customer reference
customer.Orders.Remove(order);

// To avoid null reference exceptions, we need to manually ensure both sides of the relationship are set
var customer = context.Customers.Include(c => c.Orders).FirstOrDefault(c => c.CustomerId == 1);
var newOrder = new Order();
customer.Orders.Add(newOrder);
newOrder.Customer = customer;

// Alternatively, you can use the DbSet.Local property to get all the tracked entities in memory
var orders = context.Orders.Local;
var customers = context.Customers.Local;