使用2键在Entity Framework上建立关系

Question

这个旧项目的示例结构。

public class Customs
{

    [Key,Required, Column(Order = 0)]
    public string DeclarationNo { get; set; }

    [Key, Required, Column(Order = 1)]
    public string ReceivedControlNo { get; set; }

    [Key, Required, Column(Order = 2)]
    public string MasterBL { get; set; }

    public string CustomsDetail {get;set;}

    public virtual CustomsManifest Manifest { get; set; }
 }


public class CustomsManifest
{
    [Key,Required, Column(Order = 0)]
    public string ReceivedControlNo { get; set; }
    [Key,Required, Column(Order = 1)]
    public string MasterBL { get; set; }
    public string ManifestDetail {get; set; }

    public virtual Customs Customs { get; set; }
}

如何与2键建立关系。有可能吗？

我需要加入海关和关键的钥匙。 CustomsManifest是

1. ReceivedControlNo
2. MasterBL

关系的零或一个