找到自动映射器未映射的成员 [英] Auto Mapper Unmapped members were found

问题描述

我们正在为项目使用Automapper，并且似乎随机出现以下错误:

We are using Automapper for a project, and seem to get the following error randomly:

AutoMapper.AutoMapperConfigurationException:找到了未映射的成员.在下面查看类型和成员.添加自定义映射表达式，忽略，添加自定义解析器或修改源/目标类型

AutoMapper.AutoMapperConfigurationException: Unmapped members were found. Review the types and members below. Add a custom mapping expression, ignore, add a custom resolver, or modify the source/destination type

该代码在几个月内没有被更改.我收到该错误，刷新后该错误消失了，页面工作正常.我正在使用

The code hasn't been changed in months. I get that error, refresh and the error is gone and page works fine. I'm using

Mapper.AssertConfigurationIsValid();

不确定为什么会抱怨映射不好，然后刷新，然后又可以了，有人遇到了吗?调试无济于事，因为它是随机的，有时没有错误，然后几天后它将弹出在网站上的某个地方，再返回它就可以了.该错误还会出现在随机页面上，而不是同一页面上，而不是同一映射上.

not sure why it complains the mappings are not good and then a refresh and it's fine again, has anyone run into this? Debugging doesn't help as it's random, sometimes no errors and then other days it will popup somewhere on the site, come back to it and it's fine. The error also comes up on random pages, not the same page, not the same mapping.

推荐答案

快速介绍如下面的@mrTurkay回答，可以通过以下配置解决此问题:

Quick intro edit: as @mrTurkay answers below, this can be solved with the following configuration:

cfg.ValidateInlineMaps = false;

但是，您应该首先理解为什么会发生此问题-请随时阅读.

However, you should understand why the problem occours in the first place - so feel free to read on.

当您尝试映射未为其创建映射配置的对象时，就会出现此问题.您需要记住的是，它不必是您要映射的特定对象.但其中之一是导航属性.

This problem occours when you're trying to map an object that you didn't create a mapping configuration for. What you need to keep in mind is, that it doesn't have to be the specific object you're trying to map; but one of it's navigation properties.

例如，您有一个要映射到CarDTO.cs

Say for instance you have a Car.cs that you want to map to a CarDTO.cs

Car.cs看起来像这样:

public class Car
{
  public string Color { get; set; }

  public Engine Engine { get; set; }
}

和您的DTO看起来一样，但是引用了EngineDTO:

And your DTO looks the same, but has a reference to the EngineDTO instead:

public class CarDTO
{
  public string Color { get; set; }

  public EngineDTO Engine { get; set; }
}

您按如下方式配置了映射:

You configured the mapping like this:

    Mapper.CreateMap<DTO.CarDTO, Data.Model.Car>();
    Mapper.CreateMap<Data.Model.Car, DTO.CarDTO>();

    Mapper.CreateMap<DTO.EngineDTO, Data.Model.Engine>();
    Mapper.CreateMap<Data.Model.Engine, DTO.EngineDTO>();

一切看起来都很好，对吧?但是，在您的EngineDTO中，您可能有一个导航属性，例如:

All looks fine, right? However, in your EngineDTO, you probably have a navigation property like, lets say:

public class EngineDTO
{
public List<PartDTO> Parts { get; set; }
}

因此，当Automapper从Engine映射到EngineDTO时，它也会尝试映射PartDTO，但是由于忘记了在global.asax中声明映射，因此会出现错误:

So while Automapper is Mapping from Engine to EngineDTO, it also tries to Map the PartDTO, but since you forgot to declare the mapping in the global.asax, you get the error:

AutoMapper.AutoMapperConfigurationException:未映射的成员是 成立.在下面查看类型和成员.添加自定义映射 表达式，忽略，添加自定义解析器或修改 来源/目的地类型

AutoMapper.AutoMapperConfigurationException: Unmapped members were found. Review the types and members below. Add a custom mapping expression, ignore, add a custom resolver, or modify the source/destination type

如果您不想在类上映射某些属性，则可以使用忽略":

If you don't want to map certain properties on a class, you can use Ignore:

Mapper.CreateMap<Engine, EngineDTO>()
    .ForMember(x => x.Parts, opt => opt.Ignore());

对于更强大的AutoMapper配置，我建议您使用映射配置文件，而不是直接在Global.asax中声明映射.这是一个示例:

For a more robust AutoMapper configuration, I suggest that you use mapping profiles, instead of declaring the mapping directly in Global.asax. Here is an Example:

个人资料:

public class CarProfile : Profile
{
    public CarProfile ()
    {
        CreateMap<Car, CarDTO>();
    }
}

Global.asax:

Global.asax:

Mapper.Initialize(cfg =>
{
     cfg.AddProfile<CarProfile>();
}

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