Question

也许这是设计的，但我们最初并不期望automapper能够捕获并忽略映射中的所有NullReferenceExceptions。我们主要使用MapFrom并创建有时复杂的表达式。如果有任何异常，甚至是NullReferenceException，我们希望这些映射失败，但我们不能让AutoMapper这样做。有没有办法让automapper不忽略所有这些异常，而不必为每个案例编写自定义值解析器？这对我们来说意味着很多额外的代码，事实上，如果不首先使用automapper，它可能会减少代码。

这些是我们期望全部通过的测试：

[TestFixture]
public class Tests
{
    [SetUp]
    public void Setup() { Mapper.Reset(); }

    [Test]
    public void ShouldThrowMappingExceptionUsingMapFromExpression()
    {
        Mapper.CreateMap<Source, Destination>()
            .ForMember(d => d.DestinationMember, o => o.MapFrom(s => s.SourceMember.SourceProperty))
            ;

        Assert.Throws<AutoMapperMappingException>(() => Mapper.Map<Source, Destination>(new Source()));
    }

    [Test]
    public void ShouldThrowMappingExceptionUsingResolveUsingExpression()
    {
        Mapper.CreateMap<Source, Destination>()
            .ForMember(d => d.DestinationMember, o => o.ResolveUsing(s => s.SourceMember.SourceProperty))
            ;

        Assert.Throws<AutoMapperMappingException>(() => Mapper.Map<Source, Destination>(new Source()));
    }

    [Test]
    public void ShouldThrowMappingExceptionUsingResolverInstance()
    {
        Mapper.CreateMap<Source, Destination>()
            .ForMember(d => d.DestinationMember, o => o.ResolveUsing(new TestValueResolver()).FromMember(s => s.SourceMember))
            ;

        Assert.Throws<AutoMapperMappingException>(() => Mapper.Map<Source, Destination>(new Source()));
    }

    [Test]
    public void ShouldThrowMappingExceptionUsingResolverType()
    {
        Mapper.CreateMap<Source, Destination>()
            .ForMember(d => d.DestinationMember, o => o.ResolveUsing<TestValueResolver>().FromMember(s => s.SourceMember))
            ;

        Assert.Throws<AutoMapperMappingException>(() => Mapper.Map<Source, Destination>(new Source()));
    }

}

public class Destination
{
    public string DestinationMember { get; set; }
}

public class Source
{
    public SourceChild SourceMember { get; set; }
}

public class SourceChild
{
    public string SourceProperty { get; set; }
}

public class TestValueResolver : ValueResolver<SourceChild, string>
{
    protected override string ResolveCore(SourceChild source)
    {
        return source.SourceProperty;
    }
}

Answer 1

此行为现已在AutoMapper中更改！： - ）

https://github.com/AutoMapper/AutoMapper/issues/122

AutoMapper捕获并忽略NullReferenceException

1 个答案: