AutoMapper映射报错：从含IEnumerable属性对象映射到IEnumerable实体

使用AutoMapper进行对象映射时，执行代码_mapper.Map<IEnumerable<SchedulerEventViewModel>>(response);（其中response为GetWorkShiftCurrentCachedResponse类型）抛出如下错误：

System.TypeLoadException: Method 'GetEnumerator' in type 'Proxy_System.Collections.Generic.IEnumerable`1[[StoreManager.Web.Areas.Turnazione.Models.SchedulerEventViewModel, StoreManager.Web, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]48512780' from assembly 'AutoMapper.Proxies, Version=0.0.0.0, Culture=neutral, PublicKeyToken=be96cd2c38ef1005' does not have an implementation.

但直接映射response的events属性：_mapper.Map<IEnumerable<SchedulerEventViewModel>>(response.events);可正常运行。现需配置正确的AutoMapper映射规则，实现直接从整个response对象映射为IEnumerable<SchedulerEventViewModel>，无需在映射时指定events属性。

类定义 #

public class GetWorkShiftCurrentCachedResponse
{
    public IEnumerable<SchedulerEventCommandModel> events { get; set; }
}

public class SchedulerEventCommandModel
{
    public string Title { get; set; }
    public string Description { get; set; }
    public DateTime Start { get; set; }
    public DateTime End { get; set; }
    public string RecurrenceRule { get; set; }
    public string RecurrenceID { get; set; }
    public string RecurrenceException { get; set; }
    public bool IsAllDay { get; set; }
    public int id { get; set; }
    public int dipendenteId { get; set; }
    public int idReparto { get; set; }
    public int idPuntoVendita { get; set; }
    public string stato { get; set; }
}

public class SchedulerEventViewModel
{
    public string Title { get; set; }
    public string Description { get; set; }

    private DateTime start;
    public DateTime Start
    {
        get
        {
            return start;
        }
        set
        {
            start = value.ToUniversalTime();
        }
    }

    private DateTime end;
    public DateTime End
    {
        get
        {
            return end;
        }
        set
        {
            end = value.ToUniversalTime();
        }
    }

    public string RecurrenceRule { get; set; }
    public string RecurrenceID { get; set; }
    public string RecurrenceException { get; set; }
    public bool IsAllDay { get; set; }

    //自定义字段
    public int id { get; set; }
    public int dipendenteId { get; set; }
    public int idReparto { get; set; }
    public int idPuntoVendita { get; set; }
    public string stato { get; set; }
}

当前映射配置 #

CreateMap<SchedulerEventViewModel, SchedulerEventCommandModel>().ReverseMap();
CreateMap<GetWorkShiftCurrentCachedResponse, IEnumerable<SchedulerEventViewModel>>().ReverseMap()
                .ForMember(o => o.events, b => b.MapFrom(x => x));
//尝试过更明确的写法
//CreateMap<GetWorkShiftCurrentCachedResponse, IEnumerable<SchedulerEventViewModel>>().ReverseMap()
//                .ForMember(o => o.events, b => b.MapFrom(x => x.AsEnumerable()));
//CreateMap<GetWorkShiftCurrentCachedResponse, IEnumerable<SchedulerEventViewModel>>().ReverseMap()
//                .ForMember(o => o.events, b => b.MapFrom(x => x.AsEnumerable<SchedulerEventViewModel>()));

AutoMapper无法直接将普通类映射到IEnumerable<T>接口，因为它无法为接口生成合法的代理实现，这就是你遇到GetEnumerator方法未实现错误的核心原因。以下是两种可行的配置方案：

方案1：使用ConvertUsing定义自定义转换逻辑 #

直接指定转换时的具体逻辑，明确从response中提取events并完成映射：

CreateMap<SchedulerEventViewModel, SchedulerEventCommandModel>().ReverseMap();

// 正向映射：从GetWorkShiftCurrentCachedResponse转成ViewModel集合
CreateMap<GetWorkShiftCurrentCachedResponse, IEnumerable<SchedulerEventViewModel>>()
    .ConvertUsing(src => _mapper.Map<IEnumerable<SchedulerEventViewModel>>(src.events));

// 反向映射：从ViewModel集合转成GetWorkShiftCurrentCachedResponse
CreateMap<IEnumerable<SchedulerEventViewModel>, GetWorkShiftCurrentCachedResponse>()
    .ConvertUsing(src => new GetWorkShiftCurrentCachedResponse 
    { 
        events = _mapper.Map<IEnumerable<SchedulerEventCommandModel>>(src) 
    });

方案2：使用MapFrom简化配置 #

如果不需要复杂逻辑，可直接指定映射的源属性：

CreateMap<SchedulerEventViewModel, SchedulerEventCommandModel>().ReverseMap();

// 正向映射：直接将response的events属性作为映射源
CreateMap<GetWorkShiftCurrentCachedResponse, IEnumerable<SchedulerEventViewModel>>()
    .MapFrom(src => src.events);

// 反向映射：将集合直接赋值给response的events属性
CreateMap<IEnumerable<SchedulerEventViewModel>, GetWorkShiftCurrentCachedResponse>()
    .ForMember(dest => dest.events, opt => opt.MapFrom(src => src));

注意事项 #

• 避免直接将类映射到接口类型（如IEnumerable<T>），AutoMapper更擅长处理具体类之间的映射，这类包装类转集合的场景需要自定义转换规则。
• 确保SchedulerEventCommandModel与SchedulerEventViewModel之间的映射已正确配置（你当前的ReverseMap()已满足需求）。

内容的提问来源于stack exchange，提问作者pinale