实体框架6& TPH继承：默认情况下，将具有相同名称的属性映射到同一列 [英] Entity Framework 6 & TPH inheritance: Map properties with the same name to same column by default

问题描述

 公共类MyContext：DbContext 
 {
 public DbSet< Device>设备{get;组; 
 
 protected override void OnModelCreating（DbModelBuilder modelBuilder）
 {
 modelBuilder.Entity< ABatteryPoweredDevice>（）。Property（c => c.BatteryLevel）.HasColumnName（BatteryLevel ）; 
 modelBuilder.Entity< ADifferentBatteryPoweredDevice>（）。Property（c => c.BatteryLevel）.HasColumnName（BatteryLevel）; 
} 
} 
  

BatteryLevel 不属于 Device 基类的一部分 - 它是实现接口合同实现的派生类的属性。

有可能使这是默认行为，而不是为每个派生类添加一个新的映射？

解决方案

使用自定义代码优先公约（可从EF6起），将其排除

$ b

  protected override void OnModelCreating（DbModelBuilder modelBuilder）
 {
 //您的代码在$ b $之前b modelBuilder.Properties（）。配置（prop => prop.HasColumnName（prop.ClrPropertyInfo.Name））; 
 //你的代码在
之后
  

这个映射具有相同名称的属性在不同的派生类型到同一个表列，没有明确的调用，如问题中提到的那样。

As of EF6 it is possible to do something like this when configuring Entity mappings using Table Per Hierarchy inheritance:

public class MyContext : DbContext 
{
    public DbSet<Device> Devices { get; set; }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Entity<ABatteryPoweredDevice>().Property(c => c.BatteryLevel).HasColumnName("BatteryLevel");
        modelBuilder.Entity<ADifferentBatteryPoweredDevice>().Property(c => c.BatteryLevel).HasColumnName("BatteryLevel");
    }
}

BatteryLevel is not part of the Device base class- it is a property of the derived classes implemented to fulfill an interface contract.

Is it possible to make this the default behavior as opposed to having to add a new mapping for each derived class?

解决方案

Used Custom Code First Conventions, which are available from EF6 onwards, to sort this out:

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        //your code before
        modelBuilder.Properties().Configure(prop => prop.HasColumnName(prop.ClrPropertyInfo.Name));
        //your code after
    }

This maps properties with the same name in different derived types to the same table column without explicit calls like those mentioned in the question.

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