Mapping:
.ForMember(dest => dest.DisplayName, opt =>
{
opt.PreCondition(location => location.Parent != null);
opt.MapFrom(src => src.Name + ", " + src.Parent.Name);
})
.ForMember(dest => dest.DisplayName, opt =>
{
opt.PreCondition((src, dest, context) => dest.DisplayName == null);
opt.MapFrom(src => src.Name);
})
Expected result:
If the first condition is met don't override the mapping.
What actually happens:
The second mapping is overriding the first mapping.
How can I solve this?
It doesn't work because you are overwriting previous mapping expressions calling another ForMember() for the same member, which is your case is DisplayName. Consider such case:
.ForMember(d => d.DisplayName, o => o.MapFrom(s => "1"))
.ForMember(d => d.DisplayName, o => o.MapFrom(s => "2"))
.ForMember(d => d.DisplayName, o => o.MapFrom(s => "3"));
Which value will be mapped to DisplayName?
3
So in your case, your first conditional mapping expression is overwriten by the second one. To make it work, join the conditional mapping into one mapping expression:
.ForMember(
dest => dest.DisplayName,
opts => opts.MapFrom((src, dest) =>
{
if (src.Parent != null)
{
return string.Join(", ", src.Name, src.Parent.Name);
}
else
{
if (dest.DisplayName is null)
{
return src.Name;
}
else
{
return "Some other value when no conditions were met.";
}
}
}));
It would be a cool feature to have but I don't see it anywhere in Automapper documentation.
This should however work in your case if the logic is not more complex.
.ForMember(dest => dest.DisplayName, opt =>
{
opt.MapFrom(src => src.Name + (location.Parent != null ? ", " + src.Parent.Name : null));
})
Related
I am using Automapper for mapping my dtos. I have a tricky scenario where I want to map on condition.
if (countryCode == "")
CreateMap<src, dest>()
.ForMember(dest => dest.CountryOriginCode,
act => act.MapFrom(src =>
src.FirstOrDefault(k => k.Key == "CountryExportCode").Value))
else
CreateMap<src, dest>()
.ForMember(dest => dest.CountryOriginCode,
act => act.MapFrom(src =>
src.FirstOrDefault(k => k.Key == "CountryOriginCode").Value))
I have 2 requirements here.
I want to map it conditionally
How can I get the value of CountryCode which is in another object say CountryObject
Edit -
CreateMap<country, countryDto>()
.ForMember(dest => dest.CountryCode, act => act.MapFrom(src => src.CountryCode))
CreateMap<src, dest>()
.ForMember(
dest => dest.CountryOriginCode,
act => act.MapFrom(src => countryCode == CountryCode ? // Observer the CountryCode , I need it from above
src.FirstOrDefault(k => k.Key == "CountryExportCode").Value:
src.FirstOrDefault(k => k.Key == "CountryOriginCode").Value)
)
How about this
CreateMap<src, dest>()
.ForMember(
dest => dest.CountryOriginCode,
act => act.MapFrom(src => countryCode == "" ?
src.FirstOrDefault(k => k.Key == "CountryExportCode").Value:
src.FirstOrDefault(k => k.Key == "CountryOriginCode").Value)
)
I'm fairly new to AutoMapper and want to know how to set a destination member to a value based on a DIFFERENT source property value and if that value is null I just want to apply the default behaviour of Automapper (keep destination value when the source is null)
CreateMap<ClassA, ClassA>()
.ForMember(dest => dest.PropertyA, opt =>
opt.MapFrom(src => src.PropertyB!= null ? null : opt.UseDestinationValue())
)
This doesn't work (don't compile) the opt.UseDestinationValue() , what option can I use here?
Please help
Try setting a precondition for mapping destination property.
CreateMap<ClassA, ClassA>().ForMember(dest => dest.PropertyA, opt => opt.PreCondition((src, dest) => src.PropertyB != null));
This will map PropertyA only when PropertyB is not null. I did try a quick sample which gave the desired result.
I think you can use the PreCondition option For Mapping Property
CreateMap<ClassA, ClassA>()
.ForMember(dest => dest.PropertyA, opt => {
opt.PreCondition(src => src.PropertyB!= null);
opt.MapFrom(src => src.PropertyB);
});
Hope to help you
You can do as follows:
var configuration = new MapperConfiguration(cfg => {
cfg.CreateMap<ClassA,ClassA>()
.ForMember(dest => dest.PropertyA, opt => opt.Condition(src => (src.PropertyB!= null)));
});
Or as follows:
var configuration = new MapperConfiguration(cfg => {
cfg.CreateMap<ClassA,ClassA>()
.ForMember(dest => dest.PropertyA, opt => {
opt.PreCondition(src => (src.PropertyB!=null));
opt.MapFrom(src => src.PropertyB); // mapping process takes place here
});
});
But the difference is that, the later runs sooner in the mapping process.
There is an excellent documentation in setting conditions for automapper:
https://docs.automapper.org/en/stable/Conditional-mapping.html
I want to map most properties of the current object (this a FinancialBase instance) to another object (the 'destination' object, the schedule, an instance of a Schedule class). However, I need to keep a small set of the destination's properties.
I've got it working with a 'hack' where I capture the values explicitly then use these in the AfterMap function. See example code.
var id = schedule.Id;
var parentId = schedule.ParentId;
var scheduleNo = schedule.ScheduleNo;
var schName = schedule.SchName;
var config = new MapperConfiguration(
cfg => cfg.CreateMap<FinancialBase, Schedule>()
.ForMember(d => d.Id, opt => opt.Ignore())
.ForMember(d => d.ParentId, opt => opt.Ignore())
.ForMember(d => d.ScheduleNo, opt => opt.Ignore())
.ForMember(d => d.SchName, opt => opt.Ignore())
.AfterMap((s, d) => d.Id = id)
.AfterMap((s, d) => d.ParentId = parentId)
.AfterMap((s, d) => d.ScheduleNo = scheduleNo)
.AfterMap((s, d) => d.SchName = schName));
var mapper = config.CreateMapper();
schedule = mapper.Map<Schedule>(this);
I would prefer not to use the first four lines of my example but instead have them included using a conventional AutoMapper lambda expression. Possible?
I'd just use mapping to an existing object:
var existingSchedule = new Schedule()
{
Id = 12,
ParentId = 34,
ScheduleNo = 56,
SchName = "Foo",
};
var schedule = mapper.Map(this, existingSchedule);
And in the configuration leave the Ignore() lines but remove those with AfterMap() as they are no longer needed:
var config = new MapperConfiguration(
cfg => cfg.CreateMap<FinancialBase, Schedule>()
.ForMember(d => d.Id, opt => opt.Ignore())
.ForMember(d => d.ParentId, opt => opt.Ignore())
.ForMember(d => d.ScheduleNo, opt => opt.Ignore())
.ForMember(d => d.SchName, opt => opt.Ignore()));
Is it possible to use a custom value resolver in automapper only if a certain condition is met?
In my case I only want to update the value with the custom value resolver if the destination is not null.
This is an example of my code. Basically I need to add the condition onto this. Is it possible?
Mapper.CreateMap<ResponseXml, MyModel>()
.ForMember(dest => dest.FirstName,
op => op.ResolveUsing<ResponseXmlValueResolver>()
.FromMember(x => x.data.FirstOrDefault(y => y.name == "name")))
I think Eris' solution would have work; It was just grammatical errors.
Mapper.CreateMap<ResponseXml, MyModel>()
.ForMember(dest => dest.FirstName,
op => {
op.Condition(src => src != null);
op.ResolveUsing<ResponseXmlValueResolver>();
.FromMember(x => x.data.FirstOrDefault(y => y.name == "name"));
});
Is this what you wanted?
If the destination is null, the mapping will be ignore.
If the destination is null, the mapping (with the customer resolved) will be apply.
As Conditions are evaluated after resolving member, like it's said here, none of the previous answers are correct.
You should rather use PreCondition this way:
Mapper.CreateMap<ResponseXml, MyModel>()
.ForMember(dest => dest.FirstName,
op => {
op.PreCondition(src => src != null);
op.ResolveUsing<ResponseXmlValueResolver>();
.FromMember(x => x.data.FirstOrDefault(y => y.name == "name"));
});
Will this work? (I don't have a windows box in front of me at the moment)
Mapper.CreateMap<ResponseXml, MyModel>()
.ForMember(dest => dest.FirstName,
op => op.Condition(src => src != null)
.ResolveUsing<ResponseXmlValueResolver>()
.FromMember(x => x.data.FirstOrDefault(y => y.name == "name")))
I'm using automapper and I would like to know if it's possible to ignore a mapping of a field when that's null.
That's my code:
.ForMember(dest => dest.BusinessGroup_Id,
opt => opt.MapFrom(src => (int)src.BusinessGroup))
src.BusinessGroup type = "enum"
dest.BusinessGroup_Id = int
The objective it's to ingore that Mapping if src.BusinessGroup = null.
I think NullSubstitute option will do the trick
.ForMember(d => d.BusinessGroup_Id, o => o.MapFrom(s => (int?)s.BusinessGroup));
.ForMember(d => d.BusinessGroup_Id, o => o.NullSubstitute(0));
BTW you can write your conditions in mapping action:
.ForMember(d => d.BusinessGroup_Id,
o => o.MapFrom(s => s.BusinessGroup == null ? 0 : (int)s.BusinessGroup));
UPDATE if you cannot assign some default value to your property, you can just ignore it and map only not nulls:
.ForMember(d => d.BusinessGroup_Id, o => o.Ignore())
.AfterMap((s, d) =>
{
if (s.BusinessGroup != null)
d.BusinessGroup_Id = (int)s.BusinessGroup;
});