是通用类不支持作为实体框架模型？ [英] Are generic classes not supported as models in Entity Framework?

问题描述

我试图做这样的事情：

public class TrackerContext : DbContext
{
    public bool TrackNewValues { get; set; }

    public TrackerContext(bool trackNewValues = false)
        : base()
    {
        TrackNewValues = trackNewValues;
    }

    public TrackerContext(string connectinString, bool trackNewValues = false)
        : base(connectinString)
    {
        TrackNewValues = trackNewValues;
    }

    public DbSet<AuditLog<string>> AuditLog { get; set; }
    public DbSet<AuditLogChild> LogChildren { get; set; }
}



public class AuditLog<UserIdOrUserNameColumnType>
{
    public AuditLog()
    {
        Children = new List<AuditLogChild>();
    }

    [Key]
    public Guid AuditLogID { get; set; }

    public UserIdOrUserNameColumnType UserId { get; set; }

    [Required]
    public DateTimeOffset EventDateUTC { get; set; }
}

不过，我想 DbSet＆LT;审计日志＆LT;串GT;＆GT; 不支持。我得到这个错误：

But I guess DbSet<AuditLog<string>> is not supported. I get this error:

附加信息：类型'TrackerEnabledDbContext.AuditLog`1 [System.String]'没有映射。
      检查类型尚未明确使用方法忽略或NotMappedAttribute数据注解排除。
      验证被定义为一类的类型，不是原始或通用的，并且不从EntityObject继承

Additional information: The type 'TrackerEnabledDbContext.AuditLog`1[System.String]' was not mapped. Check that the type has not been explicitly excluded by using the Ignore method or NotMappedAttribute data annotation. Verify that the type was defined as a class, is not primitive or generic, and does not inherit from EntityObject.

有没有我可以实现任何方式公共DbSet＆LT;审计日志＆LT;串GT;＆GT;审计日志{搞定;组; } ？

Is there any ways I can implement public DbSet<AuditLog<string>> AuditLog { get; set; } ?

推荐答案

由于实体框架根本不支持泛型类型的实体不能映射泛型类型。
当使用EF code-First方法，你需要记住，你应该型号你的 POCO类，使实体框架创建的的=http://msdn.microsoft.com/en-us/library/vstudio/dd468057 ％28V = VS.100％29.aspx相对=nofollow> POCO代理。

You cannot map the generic type because Entity Framework simply doesn't support generic Entity types. When using the EF Code-First approach you need to remember that you should model your POCO classes within the constraints that allow Entity Framework to create POCO proxies.

这意味着，短期内来讲，这样的类：

This means, shortly speaking that such a class:

• 如果不包含任何属性


• 不应该是通用


• 应该是公开的


• 不得被密封


• 绝不能是抽象


• 必须有一个没有参数公共或受保护的构造

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