NetCore+AutoMapper多個對象映射到一個Dto對象
- 2019 年 10 月 3 日
- 筆記
目錄
一、定義源映射類和被映射類DTO
二、注入AutoMapper
三、配置映射
四、調用AutoMapper完成賦值
五、運行測試
一、定義源映射對象
為了體現AutoMapper映射特性，在SocialAttribute中的Name屬性沒有定義在People中，People的Ear屬性也不存在與SocialAttribute和PhysicalAttribute中。
程式碼如下：
/// <summary> /// 身體屬性 /// </summary> public class PhysicalAttribute { public string Eye { get; set; } public string Mouth { get; set; } }
PhysicalAttribute
/// <summary> /// 社會屬性 /// </summary> public class SocialAttribute { public int Age { get; set; } public bool IsMarried { get; set; } public string Name { get; set; } }
SocialAttribute
public class PeopleDto { public string Eye { get; set; } public string Mouth { get; set; } public string Ear { get; set; } public int Age { get; set; } public bool IsMarried { get; set; } }
PeopleDto
二、注入AutoMapper
例子中使用的IOC容器是Autofac，不使用Autofac的話，僅用NetCore框架集成的IOC容器也可以實現。
註冊AutoMapper必要組件：
public static class AutoMapperInjection { public static ContainerBuilder LoadAutoMapper(this ContainerBuilder builder) { builder.RegisterType<MapperConfigurationExpression>().SingleInstance(); builder.Register(m => { var mapperConfigurationExpression = m.Resolve<MapperConfigurationExpression>(); var instance = new MapperConfiguration(mapperConfigurationExpression); return instance; }); builder.Register(m => { var mapperConfiguration = m.Resolve<MapperConfiguration>(); return mapperConfiguration.CreateMapper(); }); return builder; } }
三、配置映射
ForMember：映射兩個類之間的屬性關係。
People類中的Ear屬性並不存在於任何映射源類中，我們可以使用ForMember(m => m.Ear, n => n.Ignore())忽略該屬性，當然也可以不寫這段程式碼，對AutoMapper不會有任何影響，但是為了後期維護更方便，我比較習慣將Dto類的屬性寫全。
SocialAttribute類中的Name屬性不存在與People類中，直接忽略它，Name也不會被AutoMapper賦值。
public class AutoMapperProfile: Profile { public void Mapping(ILifetimeScope scope) { var expression = scope.Resolve<MapperConfigurationExpression>(); expression.CreateMap<PhysicalAttribute, PeopleDto>() .ForMember(m => m.Eye, n => n.MapFrom(s => s.Eye)) .ForMember(m => m.Mouth, n => n.MapFrom(s => s.Mouth)); //.ForMember(m => m.Ear, n => n.Ignore()); expression.CreateMap<SocialAttribute, PeopleDto>() .ForMember(m => m.Age, n => n.MapFrom(s => s.Age)) .ForMember(m => m.IsMarried, n => n.MapFrom(s => s.IsMarried)); } }
四、調用AutoMapper完成賦值
調用AutoMapper，將PhysicalAttribute和SocialAttribute的值賦給PeopleDto
public class DtoHelper { private IMapper mapper; public DtoHelper(IMapper _mapper) { mapper = _mapper; } public PeopleDto GetDto(PhysicalAttribute physical,SocialAttribute social) { PeopleDto peopleDto = new PeopleDto(); mapper.Map(social, mapper.Map(physical, peopleDto)); return peopleDto; } }
五、運行測試
測試框架使用的xUnit
public class DtoHelperTest { [Fact] public void GetDto() { //moke ContainerBuilder builder = new ContainerBuilder(); builder.LoadAutoMapper(); builder.RegisterType<AutoMapperProfile>(); IContainer Container = builder.Build(); using (var scope = Container.BeginLifetimeScope()) { scope.Resolve<AutoMapperProfile>().Mapping(scope); PeopleDto result = new PeopleDto() { Eye = "雙眼皮", Mouth = "紅潤", Age = 18, IsMarried = false }; PhysicalAttribute physical = new PhysicalAttribute() { Eye = "雙眼皮", Mouth = "紅潤" }; SocialAttribute social = new SocialAttribute() { Name = "張三", IsMarried = false, Age = 18 }; PeopleDto output = new DtoHelper(scope.Resolve<IMapper>()).GetDto(physical, social); //Assert.Same(result, output); Assert.Equal(JsonConvert.SerializeObject(result), JsonConvert.SerializeObject(output)); } } }
通過測試！
參考項目：https://github.com/FB208/CodeSpace/tree/master/CodeSpace.CSharp/WebMvc/DemoClass/AutoMapperDemo
