覆盖实体框架实体属性
我在 EF 中有一个名为 Profile 的实体，我想向该实体的 FirstName 属性添加数据注释属性。所以，我创建了一个新的部分类，如下所示；
public partial class Profile : EntityObject
{
[Required]
[Display(Name = "First Name")]
[EdmScalarPropertyAttribute(EntityKeyProperty = false, IsNullable = false)]
[DataMemberAttribute()]
override public global::System.String FirstName
{
get
{
return _FirstName;
}
set
{
OnFirstNameChanging(value);
ReportPropertyChanging("FirstName");
_FirstName = StructuralObject.SetValidValue(value, false);
ReportPropertyChanged("FirstName");
OnFirstNameChanged();
}
}
}
但我明白了；
类型“
CC.Models.Profile”已包含“FirstName”的定义
有什么想法吗？
问候，
瑞安
I have an entity in EF named Profile and I would like to add data annotation attributes to the FirstName property of this entity. So, I created a new partial class like so;
public partial class Profile : EntityObject
{
[Required]
[Display(Name = "First Name")]
[EdmScalarPropertyAttribute(EntityKeyProperty = false, IsNullable = false)]
[DataMemberAttribute()]
override public global::System.String FirstName
{
get
{
return _FirstName;
}
set
{
OnFirstNameChanging(value);
ReportPropertyChanging("FirstName");
_FirstName = StructuralObject.SetValidValue(value, false);
ReportPropertyChanged("FirstName");
OnFirstNameChanged();
}
}
}
But I am getting this;
The type '
CC.Models.Profile' already contains a definition for 'FirstName'
Any ideas?
Regards,
Ryan
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（3）
不幸的是你不能这样改变它。您必须创建一个元数据类并将元数据属性添加到该类。请参阅以下链接：
http://msdn.microsoft.com/en-us/ Library/system.componentmodel.dataannotations.metadatatypeattribute.aspx
看看 此链接可查看生成元数据类的一些问题，我通常做的是如果我更改了一些内容，我只是重新生成通过添加新服务并随后删除该服务来创建元数据类，然后合并这两个服务，保留旧的更改并保留新添加的实体。
You unfortunately can't change it like that. You have to create a metadata class and add the metadata attributes to that class. See below link:
http://msdn.microsoft.com/en-us/library/system.componentmodel.dataannotations.metadatatypeattribute.aspx
Have a look at this link to see some issues with generating a metadata class, what I normally do is if I change something I just regenerate the metadataclass by adding a new service and deleting the service afterwards and then merge the two keeping my old changes and keeping the newly added entities.
遗憾的是，您无法向 POCO 中生成的属性添加任何注释。
一种可能的解决方法是修改 TT 模板，为您只想定位的给定属性+实体添加所需的自定义注释。
我在之前的项目中，当我想使用Enterprise Library来实现验证时，也遇到了同样的问题。我最终创建了一个分部类并编写了用注释修饰的方法。
在您的情况下，您可以尝试在分部类中创建一个属性（具有不同的名称），该属性返回顶部带有注释的 EF 实体属性。
You cannot unfortunately add any annotations to the properties generated in the POCO.
A possible workaround is to modify the TT template to add the custom annotation that you want for the given property+entity that you want to target only.
I had the same issue in a previous project when I wanted to use the Enterprise Library to implement validation. I ended up creating a partial class and writing methods decorated with annotations instead.
In your case, you can try creating in a partial class a property (with a different name) that returns the EF entity property with an annotation on top.
我相信您也必须将您的财产标记为部分财产。
实际上我认为您也想删除覆盖（因为您没有覆盖父属性。）
I believe you have to mark your property as partial as well.
Actually I think you also will want to remove the override (because you aren't overriding a parent property.)