所以我除了通常的DTO之外还有一些商业映射器,我试图用最少量的映射代码映射它们。
设置
public class Target {
public string propA { get; set; }
public string propB { get; set; }
public string propC { get; set; }
public string propD { get; set; }
public string propE { get; set; }
public List<KeyValuePair> Tokens { get; set; }
}
public class Source {
public SomeClass SomeClass { get; set; }
public AnotherClass AnotherClass { get; set; }
}
public class SomeClass {
public string propA { get; set; }
public string propB { get; set; }
public string propDifferent { get; set; }
public List<KeyValuePair> Tokens { get; set; }
}
public class AnotherClass {
public string propC { get; set; }
public string propD { get; set; }
public List<KeyValuePair> Tokens { get; set; }
}
Mapper配置
Mapper.CreateMap<SomeClass, Target>()
.ForMember(dest => dest.propE, opt => opt.MapFrom(src => src.propDifferent));
Mapper.CreateMap<AnotherClass, Target>();
Mapper.CreateMap<Source, Target>()
.ForMember(dest => dest, opt => opt.MapFrom(src => src.SomeClass))
.ForMember(dest => dest, opt => opt.MapFrom(src => src.AnotherClass));
执行此操作
错误:AutoMapper.AutoMapperConfigurationException:自定义 成员配置仅支持顶级个人 一个类型的成员。
我还需要AnotherClass.Tokens
,SomeClass.Tokens
并将其添加到Target.Tokens
。
我知道我可以使用.ConvertUsing
但是我必须为每个属性定义映射,并且我失去了基于约定的匹配属性映射的优势。
是否有其他方法可以实现此目的(除了.ConvertUsing
或手动映射每个属性)?
如果不是通过 Automapper ,是否可以通过 EmitMapper 来实现?我想通过EmitMapper的PostProcessing
添加到令牌列表可能是可行的。
更新
经过一番黑客攻击后,我找到了一条路:
public static IMappingExpression<TSource, TDestination> FlattenNested<TSource, TNestedSource, TDestination>(this IMappingExpression<TSource, TDestination> expression)
{
var sourceType = typeof(TNestedSource);
var destinationType = typeof(TDestination);
var sourceProperties = sourceType.GetProperties().ToDictionary(x => x.Name.ToLowerInvariant());
var childPropName = typeof (TSource).GetProperties().First(x => x.PropertyType == sourceType).Name;
var mappableProperties = destinationType.GetProperties()
.Where(p => sourceProperties.ContainsKey(p.Name.ToLowerInvariant()) &&
sourceProperties[p.Name.ToLowerInvariant()].PropertyType ==
p.PropertyType)
.Select(p => new {DestProperty = p.Name, SrcProperty = sourceProperties[p.Name.ToLowerInvariant()].Name});
foreach (var property in mappableProperties)
{
expression.ForMember(property.DestProperty,
opt => opt.MapFrom(src => src.GetPropertyValue(childPropName).GetPropertyValue(property.SrcProperty)));
}
return expression;
}
注意:我执行Name.ToLowerInvariant()
以匹配AccountID
- &gt; AccountId
和类似的。
用法
AutoMapper.Mapper.CreateMap<Source, Target>()
.FlattenNested<Source, SomeClass, Target>()
.FlattenNested<Source, AnotherClass, Target>()
.ForMember(dest => dest.propE, opt => opt.MapFrom(src => src.propDifferent));
我发现了IMappingExpression
中我可以使用的其他一些属性,并清理了很多这些属性。我会发现它们会更新。
答案 0 :(得分:1)
这就是我解决类似问题的方法:
public static IMappingExpression<TSource, TDestination> FlattenNested<TSource, TNestedSource, TDestination>(
this IMappingExpression<TSource, TDestination> expression,
Expression<Func<TSource, TNestedSource>> nestedSelector,
IMappingExpression<TNestedSource, TDestination> nestedMappingExpression)
{
var dstProperties = typeof(TDestination).GetProperties().Select(p => p.Name);
var flattenedMappings = nestedMappingExpression.TypeMap.GetPropertyMaps()
.Where(pm => pm.IsMapped() && !pm.IsIgnored())
.ToDictionary(pm => pm.DestinationProperty.Name,
pm => Expression.Lambda(
Expression.MakeMemberAccess(nestedSelector.Body, pm.SourceMember),
nestedSelector.Parameters[0]));
foreach (var property in dstProperties)
{
if (!flattenedMappings.ContainsKey(property))
continue;
expression.ForMember(property, opt => opt.MapFrom((dynamic)flattenedMappings[property]));
}
return expression;
}
<强>用法
public class Customer
{
public string FirstName { get; set; }
public string LastName { get; set; }
public Address Address { get; set; }
}
public class Address
{
public string City { get; set; }
public string Street { get; set; }
}
public class CustomerDto
{
public string FirstName { get; set; }
public string LastName { get; set; }
public string City { get; set; }
public string Street { get; set; }
}
public class CustomerProfile : Profile
{
protected override void Configure()
{
var nestedMap = CreateMap<Address, CustomerDto>()
.IgnoreAllNonExisting();
CreateMap<Customer, CustomerDto>()
.FlattenNested(s => s.Address, nestedMap);
}
}
[TestFixture]
public class CustomerProfileTests
{
[Test]
public void Test()
{
Mapper.Initialize(c => c.AddProfile<CustomerProfile>());
Mapper.AssertConfigurationIsValid();
}
}
IgnoreAllNonExisting()
找到here。
虽然它不是通用解决方案,但对于简单的情况应该足够了。
优点是:
RecognizePrefixes
等内容。答案 1 :(得分:0)
您希望使用BeforeMap来实例化对象:
更新:
Mapper.CreateMap<Source, Target>()
.BeforeMap(( Source, Target) => {
Source.SomeClass = new SomeClass();
Source.AnotherClass = new AnotherClass();
})
.AfterMap(( Source, Target) => {
Target.SomeClass = Mapper.Map<AnotherClass, Target>(Target);
Target.AnotherClass = Mapper.Map<SomeClass, Target>(Target);
})
这将允许您在映射单个对象属性之前映射父级。
我想我迷失在基类名称中,但你可以调用mapper.Map属性来映射对象。
更新2:
基于此代码:
Mapper.CreateMap<Source, Target>()
.ForMember(dest => **dest**, opt => opt.MapFrom(src => src.SomeClass))
.ForMember(dest => **dest**, opt => opt.MapFrom(src => src.AnotherClass));
目的地试图解决一个对象。如果您只想解决这些对象的属性,那么我建议您指定它们。
Mapper.CreateMap<Source, Target>()
.ForMember(dest => dest.propA, opt => opt.MapFrom(src => src.SomeClass.propA
.ForMember(dest => dest.propB, opt => opt.MapFrom(src => src.SomeClass.propB
.ForMember(dest => dest.propC, opt => opt.MapFrom(src => src.AnotherClass.propC
.ForMember(dest => dest.propD, opt => opt.MapFrom(src => src.AnotherClass.propD