使用参数 AutoMapper 映射视图模型子项

Question

我是 AutoMapper 的新手，但遇到了问题

我有一个这样的模型。

public class StepUp {
    public string Example {get;set;}
    public string Example2 {get;set;}
    public decimal? auxValue { get;set; }
}

但我有两个 ViewModel 作为目的地

public class NuevoStepUpViewModel()
{
    public bool TieneAuxiliar { get; set; }
    public string Example { get;set; }
    public CargaDatosElectricos CargaDatosElectricos { get; set; }
}

public class CargaDatosElectricos {
    public CargaDatosElectricos(bool tieneAuxiliar)
    {
        TieneAuxiliar = tieneAuxiliar;
    }
    public readonly bool TieneAuxiliar;
    public string Example2 { get; set; }
}

我认为有些是这样的：

CreateMap<StepUp,NuevoStepUpViewModel()
    .ForMember(x => x.TieneAuxiliar, x => x.MapFrom(c => c.auxValue.HasValue))
    .ForMember(x => x.Example, x => x.MapFrom(c => c.Example))
    .ForMember(x => x.CargaDatosElectricos.Example2, x => x.MapFrom(c => c.Example2))
    .BeforeMap((x,y) => {
        x.CargaDatosElectricos = new CargaDatosElectricos(c.auxValue.HasValue);
    });

但我明白了

表达式 'x => x.CargaDatosElectricos.Example2' 必须解析为 顶级成员，而不是任何子对象的属性

我应该如何创建我的映射器配置来执行这种类型的映射？

Answer 1

您的代码存在一些错误。您可以使用AfterMap 范围而不是BeforeMap 更好地配置您的映射，以提供复杂的配置。 （我不确定，但我认为）AutoMapper 不会实例化类型为类的属性。因此，您必须在目标类 (VIewModel) 的构造函数上执行此操作，或者在 AfterMap 上执行此操作。

当TieneAuxiliar 属性为readonly 时，您将无法设置值，因此您将无法配置此属性的映射。我将其更改为公共经典属性。

在此处查看工作示例：

https://dotnetfiddle.net/HSyUVv

using System;
using AutoMapper;

public class Program
{
    public static void Main()
    {
        var config = new MapperConfiguration(cfg => 
        {
            cfg.CreateMap<StepUp, NuevoStepUpViewModel>()
                .ForMember(vm => vm.TieneAuxiliar, opt => opt.MapFrom(e => e.auxValue.HasValue))
                .ForMember(vm => vm.Example, opt => opt.MapFrom(e => e.Example))
                .AfterMap((e, vm) => 
                          {
                              vm.CargaDatosElectricos.Example2 = e.Example2;
                          });
        });

        var mapper = config.CreateMapper();

        var stepUp = new StepUp()
        {
            Example = "Example 1",
            Example2 = "Example 2",
            auxValue = 10m
        };

        var viewModel = mapper.Map<StepUp, NuevoStepUpViewModel>(stepUp);

        Console.WriteLine("SteUp was converted to ViewModel");
        Console.WriteLine("TieneAuxiliar: {0}", viewModel.TieneAuxiliar);
        Console.WriteLine("Example: {0}", viewModel.Example);
        Console.WriteLine("CargaDatosElectricos.TieneAuxiliar: {0}", viewModel.CargaDatosElectricos.TieneAuxiliar);
        Console.WriteLine("CargaDatosElectricos.Exemple2: {0}", viewModel.CargaDatosElectricos.Example2);

    }

    public class StepUp 
    {
        public string Example { get; set; }
        public string Example2 { get; set; }
        public decimal? auxValue { get; set; }
    }

    public class NuevoStepUpViewModel
    {
        public bool TieneAuxiliar { get; set; }
        public string Example { get;set; }
        public CargaDatosElectricos CargaDatosElectricos { get; set; }

        public NuevoStepUpViewModel() 
        {
            this.CargaDatosElectricos = new CargaDatosElectricos();
        }
    }

    public class CargaDatosElectricos 
    {
        public CargaDatosElectricos()
        {
        }
        public bool TieneAuxiliar { get; set; }
        public string Example2 { get; set; }
    }
}