實體框架一對一關系

Question

我首先在實體模型6代碼中使用以下模型。

public class Customer
{
    public Customer
    {

    }

    public int Id { get; set; }
    public string Name { get; set; }

    public virtual Address Address { get; set; }
}


public class Address
{
    public Address
    {

    }

    public int Id { get; set; }
    public string Street { get; set; }
    public int Number { get; set; }
    public int Country { get; set; }

    public virtual Customer Customer { get; set; }              
}

當我嘗試保存它們時，出現以下錯誤：

Unable to determine the principal end of an association between the types Customer and Address

Answer 1

您需要指定外鍵關系。 如前所述這里 ，嘗試添加[ForeignKey("CustomerId")]在public virtual Customer Customer { get; set; } public virtual Customer Customer { get; set; } public virtual Customer Customer { get; set; }和[ForeignKey("AddressId")]通過public virtual Address Address { get; set; } public virtual Address Address { get; set; } public virtual Address Address { get; set; }並將這些id字段添加到模型中。 如：

public class Customer
{
    public Customer
    {

    }

    public int Id { get; set; }
    public string Name { get; set; }
    public int Addressid { get; set; }

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


public class Address
{
    public Address
    {

    }

    public int Id { get; set; }
    public string Street { get; set; }
    public int Number { get; set; }
    public int Country { get; set; }
    public int CustomerId { get; set; }

    [ForeignKey("CustomerId")]
    public virtual Customer Customer { get; set; }              
}