列表与LT;枚举>在Aggregates EntityFramework CodeFirst [英] List<Enum> in Aggregates EntityFramework CodeFirst

问题描述

我最初使用的是枚举，这对我来说很合适，但是现在当我将该属性更改为List时，我发现这些值在数据库中没有被保存或检索，我认为CodeFirst将会为列表创建一个单独的表，并将行映射到那里，但情况并非如此，这些值既不被存储也不被保留。

Agg：

  public class Trainee：Entity 
 {
 public int TraineeId {get;组; } 
 
 public string Name {get;组; } 
 public int Age {get; set;} 
 public virtual List< CoursesTypes>课程组; 
 
} 
  

枚举：

  public enum CoursesTypes 
 {
 PHP，
网络，
} 
  

解决方案

使用标志枚举。你不需要任何额外的表。这是更快的。

在您的模型中，您可以执行

  p.CoursesOpted.Add（CoursesTypes.PHP）; 
 p.CoursesOpted.Add（CoursesTypes.PHP）; 
  

...这是错误的。有标志你会这样做

  p.CoursesOpted = CoursesTypes.PHP | CoursesTypes.Networking; 
  

http://blog.falafel.com/entity-framework-enum-flags/

I was initially using Enum in aggregates which happened to be working fine for me, but now when i changed the property to List , i find that the values are not being saved or retrieved in the database, I thought that the CodeFirst would create a separate table for the List and map the rows there, but that isn't the case, the values are neither being stored nor retreived.

Agg:

public class Trainee: Entity
    {
        public int TraineeId { get; set; }

        public string Name { get; set; }
        public int Age { get; set;}
        public virtual List<CoursesTypes> CoursesOpted { get; set; }

    }

Enum:

 public enum CoursesTypes
    {
        PHP,
        Networking,
    }

解决方案

Use Flag Enum. You dont need any additional tables. It is much more faster.

In your model you can do

var person = new Trainee();
p.CoursesOpted.Add(CoursesTypes.PHP);
p.CoursesOpted.Add(CoursesTypes.PHP);

... which is wrong. With flag you will do like that

p.CoursesOpted = CoursesTypes.PHP | CoursesTypes.Networking;

http://blog.falafel.com/entity-framework-enum-flags/

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