实体框架6代码第一 - 自定义类型映射 [英] Entity Framework 6 Code First - Custom Type Mapping

问题描述

我在我的域中使用一些模型，这些模型不是非常序列化或映射友好的，例如来自 System.Net。命名空间的结构体或类。

现在我想知道是否可以在Entity Framework中定义自定义类型映射。

Pseudo：

  public class PhysicalAddressMap：ComplexType< PhysicalAddress>（）{
 public PhysicalAddressMap 
 
 this.Map（x => new {x.ToString（：）}）; 
 this.From（x => PhysicalAddress.Parse（x））; 
} 
} 
  

希望的结果： / p>

  SomeEntityId SomeProp PhysicalAddress SomeProp 
 ------------------- ----------------------------------------------- 
 4 blubb 00：00：00：C0：FF：EE blah 
 
 ^ 
 | 
 // PhysicalAddress被映射为string
 //并且将被
检索// PhysicalAddress.Parse（string value）
  pre> 
 
解决方案
包装 NotMapped 属性> PhysicalAddress ，其中包含处理转换的映射字符串属性：
  ] 
 [MaxLength（17）] 
 public string PhysicalAddressString 
 {
 get 
 {
 return PhysicalAddress.ToString 
} 
 set 
 {
 PhysicalAddress = System.Net.NetworkInformation.PhysicalAddress.Parse（value）; 
} 
} 
 
 [NotMapped] 
 public System.Net.NetworkInformation.PhysicalAddress PhysicalAddress 
 {
 get; 
 set; 
} 
  
更新：请求关于类中包装功能的注释的示例代码
  [ComplexType] 
 public class WrappedPhysicalAddress 
 {
 [MaxLength（17）] 
 public string PhysicalAddressString 
 {
 get 
 {
 return PhysicalAddress == null？ null：PhysicalAddress.ToString（）; 
} 
 set 
 {
 PhysicalAddress = value == null？ null：System.Net.NetworkInformation.PhysicalAddress.Parse（value）; 
} 
} 
 
 [NotMapped] 
 public System.Net.NetworkInformation.PhysicalAddress PhysicalAddress 
 {
 get; 
 set; 
} 
 
 public static implicit operator string（WrappedPhysicalAddress target）
 {
 return target.ToString（）; 
} 
 
 public static implicit operator System.Net.NetworkInformation.PhysicalAddress（WrappedPhysicalAddress target）
 {
 return target.PhysicalAddress; 
} 
 
 public static implicit operator WrappedPhysicalAddress（string target）
 {
 return new WrappedPhysicalAddress（）
 {
 PhysicalAddressString = target 
}; 
} 
 
 public static implicit operator WrappedPhysicalAddress（System.Net.NetworkInformation.PhysicalAddress target）
 {
 return new WrappedPhysicalAddress（）
 {
 PhysicalAddress = target 
}; 
} 
 
 public override string ToString（）
 {
 return PhysicalAddressString; 
} 
} 
  
 
I'm using some models inside my domain which are not very serialization- or mapping-friendly, such as structs or classes from the System.Net.* namespace.

Now I'm wondering if it's possible to define custom type mappings in Entity Framework.

Pseudo:
public class PhysicalAddressMap : ComplexType<PhysicalAddress>() {
    public PhysicalAddressMap() {

        this.Map(x => new { x.ToString(":") });
        this.From(x => PhysicalAddress.Parse(x));
    }
}
Desired result:
SomeEntityId       SomeProp         PhysicalAddress    SomeProp
------------------------------------------------------------------
           4          blubb       00:00:00:C0:FF:EE        blah

                                           ^
                                           |
                             // PhysicalAddress got mapped as "string"
                             // and will be retrieved by
                             // PhysicalAddress.Parse(string value)

解决方案
wrap a NotMapped property of type PhysicalAddress with a mapped string property that handles the conversions:
    [Column("PhysicalAddress")]
    [MaxLength(17)]
    public string PhysicalAddressString
    {
        get
        {
            return PhysicalAddress.ToString();
        }
        set
        {
            PhysicalAddress = System.Net.NetworkInformation.PhysicalAddress.Parse( value );
        }
    }

    [NotMapped]
    public System.Net.NetworkInformation.PhysicalAddress PhysicalAddress
    {
        get;
        set;
    }
Update: example code for comment asking about wrapping functionality in a class
[ComplexType]
public class WrappedPhysicalAddress
{
    [MaxLength( 17 )]
    public string PhysicalAddressString
    {
        get
        {
            return PhysicalAddress == null ? null : PhysicalAddress.ToString();
        }
        set
        {
            PhysicalAddress = value == null ? null : System.Net.NetworkInformation.PhysicalAddress.Parse( value );
        }
    }

    [NotMapped]
    public System.Net.NetworkInformation.PhysicalAddress PhysicalAddress
    {
        get;
        set;
    }

    public static implicit operator string( WrappedPhysicalAddress target )
    {
        return target.ToString();
    }

    public static implicit operator System.Net.NetworkInformation.PhysicalAddress( WrappedPhysicalAddress target )
    {
        return target.PhysicalAddress;
    }

    public static implicit operator WrappedPhysicalAddress( string target )
    {
        return new WrappedPhysicalAddress() 
        { 
            PhysicalAddressString = target 
        };
    }

    public static implicit operator WrappedPhysicalAddress( System.Net.NetworkInformation.PhysicalAddress target )
    {
        return new WrappedPhysicalAddress()
        {
            PhysicalAddress = target
        };
    }

    public override string ToString()
    {
        return PhysicalAddressString;
    }
}


                        
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