有没有一种方法告诉AutoMapper忽略所有的属性,除了那些显式映射的?

我有可能从外部更改的外部DTO类,并且我希望避免显式地指定要忽略的每个属性,因为添加新属性将在尝试将它们映射到自己的对象时破坏功能(导致异常)。


当前回答

我更新了Robert Schroeder对AutoMapper 4.2的答案。对于非静态映射器配置,我们不能使用mapper . getalltypemaps(),但表达式有一个对所需的TypeMap的引用:

public static IMappingExpression<TSource, TDestination> 
    IgnoreAllNonExisting<TSource, TDestination>(this IMappingExpression<TSource, TDestination> expression)
{
    foreach (var property in expression.TypeMap.GetUnmappedPropertyNames())
    {
        expression.ForMember(property, opt => opt.Ignore());
    }
    return expression;
}

其他回答

这个问题已经问了几年了,但是这个扩展方法对我来说似乎更干净,使用当前版本的AutoMapper (3.2.1):

public static IMappingExpression<TSource, TDestination> IgnoreUnmappedProperties<TSource, TDestination>(this IMappingExpression<TSource, TDestination> expression)
{
    var typeMap = Mapper.FindTypeMapFor<TSource, TDestination>();
    if (typeMap != null)
    {
        foreach (var unmappedPropertyName in typeMap.GetUnmappedPropertyNames())
        {
            expression.ForMember(unmappedPropertyName, opt => opt.Ignore());
        }
    }

    return expression;
}

我知道这是个老问题,但是@jmoerdyk 在你的问题中:

如何在配置文件中的链式creatatemap()表达式中使用它?

你可以像这样在Profile中使用这个答案

this.IgnoreUnmapped();
CreateMap<TSource, Tdestination>(MemberList.Destination)
.ForMember(dest => dest.SomeProp, opt => opt.MapFrom(src => src.OtherProp));

我已经更新了Can Gencer的扩展,不覆盖任何现有的地图。

public static IMappingExpression<TSource, TDestination> 
    IgnoreAllNonExisting<TSource, TDestination>(this IMappingExpression<TSource, TDestination> expression)
{
    var sourceType = typeof (TSource);
    var destinationType = typeof (TDestination);
    var existingMaps = Mapper.GetAllTypeMaps().First(x => x.SourceType.Equals(sourceType) && x.DestinationType.Equals(destinationType));
    foreach (var property in existingMaps.GetUnmappedPropertyNames())
    {
        expression.ForMember(property, opt => opt.Ignore());
    }
    return expression;
}

用法:

Mapper.CreateMap<SourceType, DestinationType>()
                .ForMember(prop => x.Property, opt => opt.MapFrom(src => src.OtherProperty))
                .IgnoreAllNonExisting();

更新:注意,在9.0版本Mapper静态API被删除

The only infromation about ignoring many of members is this thread - http://groups.google.com/group/automapper-users/browse_thread/thread/9928ce9f2ffa641f . I think you can use the trick used in ProvidingCommonBaseClassConfiguration to ignore common properties for similar classes. And there is no information about the "Ignore the rest" functionality. I've looked at the code before and it seems to me that will be very and very hard to add such functionality. Also you can try to use some attribute and mark with it ignored properties and add some generic/common code to ignore all marked properties.

我更新了Robert Schroeder对AutoMapper 4.2的答案。对于非静态映射器配置,我们不能使用mapper . getalltypemaps(),但表达式有一个对所需的TypeMap的引用:

public static IMappingExpression<TSource, TDestination> 
    IgnoreAllNonExisting<TSource, TDestination>(this IMappingExpression<TSource, TDestination> expression)
{
    foreach (var property in expression.TypeMap.GetUnmappedPropertyNames())
    {
        expression.ForMember(property, opt => opt.Ignore());
    }
    return expression;
}