使用EF 4.5 Code First的复合键的MVC脚手架错误

Question

我试图弄清楚如何使MVC脚手架使用复合/复合键.

我有下表:

public class Data
{
    [Key, Column(Order = 0)]
    [ForeignKey("Note")]
    [Display(Name = "Note id")]
    public int NoteId { get; set; }

    [Key, Column(Order = 1)]
    [ForeignKey("Member")]
    [Display(Name = "Member id")]
    public int MemberId { get; set; }

    [Display(Name = "Description")]
    public string Description { get; set; }

    [Display(Name = "Note")]
    public virtual Note Note { get; set; }

    [Display(Name = "Member")]
    public virtual Member Member { get; set; }
}

当我执行脚手架的行时:

Scaffold Controller Data -Repository

我收到以下错误:

Get-PrimaryKey : Cannot find primary key property for type
Pro.Web.Models.Data'. Multiple properties appear to be 
                        primary keys: NoteId, MemberId

什么可以解决这个问题？我使用Visual Studio 2012.

谢谢.

Answer 1

命名空间PrimaryKeyLocation下的类T4Scaffolding.Core.PrimaryKeyLocators具有IPrimaryKeyLocator在PrimaryKeyLocation.cs文件本身上实现的接口列表.

阅读可用的五个实现,可以告诉您的代码将落在KeyAttributePropertyLocator实现上,返回标记为[Key] attriubute的成员,但是GetPrimaryKeyCmdlet.cs从T4引擎运行并调用PrimaryKeyLocation该类具有以下实现:

switch (primaryKeyProperties.Count)
{
    case 0:
      // Code when no key is found
    case 1:
      // Code when one key is found
    default:
      // Code when more than one key is found
      WriteError(string.Format("Cannot find primary key property for type '{0}'. 
                 Multiple properties appear to be primary keys: {1}",
                   foundClass.FullName, primaryKeyPropertyNames));
}

因此,由于switch语句不处理多个键,因此不支持组合键.解决这个问题的一种方法是实现复合键的情况,但我不知道它对t4模板本身的影响.

脚手架工具的源代码.