Automapper - 将 UTC 转换为特定时区

Question

我有以下内容，当DateUtc从 source转换为 dest 时Date，我想应用转换。现在我编写的以下转换器将适用于特定字段，因为这是指定的。

我希望我的转换器更灵活，以便我可以传递其他对象而不是SourceDto1，DestDto1例如SourceDto2和DestDto2

public class SourceDto1
{
   public DateTime DateUtc {get;set;}
}
public class DestDto1
{
   public DateTime Date {get;set;}
}
public class SourceDto2
{
   public DateTime DateUtc {get;set;}
}
public class DestDto2
{
   public DateTime Date {get;set;}
}

转换器

public class AttachmentCreatedDateResolver : IValueResolver<SourceDto1, DestDto1 DateTime>
    {

        private readonly Settings _settings;
        public AttachmentCreatedDateResolver(Settings settings)
        {
            _settings = settings;
        }


        public DateTime Resolve(SourceDto1 source, DestDto1 destination, DateTime destMember, ResolutionContext context)
        {
            TimeZoneInfo tzi = TZConvert.GetTimeZoneInfo(_settings.TimeZone);
            var converted = TimeZoneInfo.ConvertTimeFromUtc(source.DateUtc, tzi);
            return converted;
        }
    }

我想我不想为我需要在属性之间转换日期的每一对对象创建不同的解析器类。

ITypeConverter可能有用，但我不知道如何Settings从 DI注入我的

Answer 1

IMemberValueResolver您可以为此创建一个实现：

public class AttachmentCreatedDateResolver : IMemberValueResolver<object, object, DateTime, DateTime>
{
    private readonly Settings _settings;
    public AttachmentCreatedDateResolver(Settings settings)
    {
        _settings = settings;
    }

    public DateTime Resolve(object source, object destination, DateTime sourceMember, DateTime destMember, ResolutionContext context)
    {
        TimeZoneInfo tzi = TZConvert.GetTimeZoneInfo(_settings.TimeZone);
        var converted = TimeZoneInfo.ConvertTimeFromUtc(sourceMember, tzi);
        return converted;
    }
}

这与 的实现类似IValueResolver，允许您将依赖项注入解析器，同时还允许您在任何对象的成员级别使用它（请注意，源类型和目标类型设置为object）。然后，您可以为每种类型映射配置相同的解析器，如下所示：

CreateMap<SourceDto1, DestDto1>()
    .ForMember(d => d.Date, opt => opt.MapFrom<AttachmentCreatedDateResolver, DateTime>(s => s.DateUtc));
CreateMap<SourceDto2, DestDto2>()
    .ForMember(d => d.Date, opt => opt.MapFrom<AttachmentCreatedDateResolver, DateTime>(s => s.DateUtc));