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C# Automapper how to create a list with nested mapping?

I am trying to map into the list, which supposes to have two other lists inside. Is it doable? I looked at the documentation but couldn't find what I needed unless I misunderstood something.
CompanyActivityReport.cs
public int OrganisationID { get; set; }
public string OrganisationName { get; set; }
public Nullable<int> OrganisationSubTypeID { get; set; }
public CompanyActivityReportTask ReportTask{get; set;}
public CompanyActivityReportNote ReportNotes{get; set;}
My mapping:
var config = new MapperConfiguration(c =>
{
c.CreateMap<OrganisationMain,CompanyActivityReport>();
c.CreateMap<TaskMain, CompanyActivityReportTask>();
c.CreateMap<NoteMain, CompanyActivityReportNote>();
});
var mapper = new Mapper(config);
List<CompanyActivityReport> TestList = mapper.Map<List<CompanyActivityReport>>(OrganisationMainsList).ToList();

Guess you problably need to map each item individually like:
List<CompanyActivityReport> TestList = OrganisationMainsList.Select(x => mapper.Map<CompanyActivityReport>(x))
Edit: Select return a Enumerable so if you wish to mantain the behaviour a .ToList() is required:
List<CompanyActivityReport> TestList = OrganisationMainsList.Select(x => mapper.Map<CompanyActivityReport>(x)).ToList()

How do I negotiate joins and groupings based on nested properties in LINQ?

So I've got a nested data structure like this:
public class ContractTerm
{
public int ContractId { get; set; }
public string SectionId { get; set; }
public string SubsectionId { get; set; }
public string TermId { get; set; }
public int TermOrder { get; set; }
public TermItem TermNavigation { get; set; }
}
public class TermItem
{
public string SectionId { get; set; }
public string SubsectionId { get; set; }
public string TermId { get; set; }
public string Text { get; set; }
public ICollection<ContractTerm> ContractNavigation { get; set; }
}
I've also got a class to map the section/subsection pairings in a more EF-friendly way (IRL this is an enum with attribute values and a helper, but this class abstracts away some work not necessary to reproduce the issue):
public class Section
{
public string Name { get; set; }
public string SectionId { get; set; }
public string SubsectionId { get; set; }
}
Both ContractTerm and TermItem have their own collections in a DbContext, and I'm trying to get a collection of all text entries assigned to specific Sections for a given ContractId. I have the following class to contain it:
public class TextsBySection
{
public string SectionName { get; set; }
public IEnumerable<string> Texts { get; set; }
}
I want to select a collection of TextsBySection, and have something like this:
public class ContractManager
{
//insert constructor initializing MyContext here
private MyContext Context { get; }
public IEnumerable<MyOutputClass> GetTerms(int contractId, IEnumerable<Section> sections)
{
Func<string, string, IEnumerable<string>> getBySection =
(section, subsection) => context.ContractTerms.Include(x => x.TermNavigation)
.Where(x => x.ContractId == contractId
&& x.SectionId == section
&& x.SubsectionId == subsection)
.Select(x => x.TermNavigation.Text);
var result = sections.Select(x => new MyOutputClass
{
SectionName = x.Name,
Texts = getBySection(x.SectionId, x.SubsectionId)
}).ToList();
return result;
}
}
This works fine and dandy, but it hits the database for every Section. I feel like there's got to be a way to use Join and/or GroupBy to make it only query once, but I can't quite see it. Something like this, perhaps:
var result = context.ContractTerms.Include(x => x.TermNavigation)
.Where(x => x.ContractId == contractId)
.Join(sections,
term => //something
section => //something
(term, section) => /*something*/)
If all this were in SQL, selecting the necessary data would be easy:
SELECT sections.name,
term_items.text
FROM contract_terms
JOIN term_items
ON term_items.section_id = contract_terms.section_id
AND term_items.subsection_id = contract_terms.subsection_id
AND term_items.term_id = contract_terms.term_id
JOIN sections --not a real table; just corresponds to sections argument in method
ON sections.section_id = contract_terms.section_id
AND sections.subsection_id = contract_terms.subsection_id
...and then I could group the results in .NET. But I don't understand how to make a single LINQ query that would do the same thing.

I changed my answer, well I would do something like this... maybe this may help you.
public static void Main(string[] args)
{
List<Section> sections = new List<Section>();
List<ContractTerm> contractTerms = new List<ContractTerm>();
List<TermItem> termItens = new List<TermItem>();
//considering lists have records
List<TextsBySection> result = (from contractTerm in contractTerms
join termItem in termItens
on new
{
contractTerm.SectionId,
contractTerm.SubsectionId,
contractTerm.TermId
}
equals new
{
termItem.SectionId,
termItem.SubsectionId,
termItem.TermId
}
join section in sections
on new
{
contractTerm.SectionId,
contractTerm.SubsectionId
} equals new
{
section.SectionId,
section.SubsectionId
}
select
new
{
sectionName = section.Name,
termItemText = termItem.Text
}).GroupBy(x => x.sectionName).Select(x => new TextsBySection()
{
SectionName = x.Key,
Texts = x.Select(i=> i.termItemText)
}).ToList();
}

Using Lambda to insert derived attribute into IQueryable dataset

I have the following query:
IQueryable<BarcodeQuery> barcodes = db.Barcodes.Select(b => new BarcodeQuery
{
id = b.id,
category_id = b.category_id,
...
checkout = b.Checkouts.Select(c => new CheckoutChild
{
id = c.id,
loanee_id = c.loanee_id,
...
})
.Where(c => c.datein == null)
.FirstOrDefault()
});
And so on. It's based on this model:
public class BarcodeQuery
{
public int id { get; set; }
public int category_id { get; set; }
...
public CheckoutChild checkout { get; set; }
public CheckoutStatus checkoutStatus { get; set; }
}
My question is about CheckoutStatus down there at the bottom. It looks like this:
public class CheckoutStatus
{
public string status { get; set; }
public int daysUntilDue { get; set; }
public int daysOverdue { get; set; }
}
All of those values are derived from information I get from the query--none of them are in the database itself. What is the best way of inserting the CheckoutStatus values into each barcode record?
I have a function that creates the CheckoutStatus values themselves, I just don't know how to get them into the barcode records.
Thanks!

If b has just be created with new, how can b.Checkouts contain something? I do not really understadn what you are trying to do.
EF is converting the lambda expression into a SQL statement. Therefore you can only use expressions that can actually be translated to SQL. Just query the barcodes from the DB and then add the missing information to the barcodes returned in a loop.
var barcodes = db.Barcodes.Select(...).ToList();
foreach (Barcode b in barcodes) {
b.Checkouts = ...
}

Combine two lists and match values

Inside the "Distributions" variable is a key called "Deadline" which contains a date.
I would like to add "RealDeadline = i.Deadline,". All the other lines works fine, but I just cant find a way to add the last thing.
The match has to be made on AssignmentId which is the key for the whole combine. basically if the HandInData.Where(...) could just add the value of "Deadline" from "Distributions", that would do the trick..
var HandInData = db.Handins.ToList();
var Distributions = db.Distributes.ToList();
var AssignNames = HandInData.Where(a => Distributions.Any(x => x.AssignmentId == a.AssignmentId));
var StudentsHandedInDataFeed = AssignNames.Select(i => new {
*RealDeadline = i.Deadline, (this is not working..)*
Help = i.NeedHelp,
Done = i.Done,
AssName = i.Assignment.AssignmentName,
Student = i.Student.StudentName,
DeadlineInTimeformat = i.Assignment.AssignmentDeadline,
HandedInInTimeformat = i.HandedInDate,
Deadline = i.Assignment.AssignmentDeadline.ToString(),
HandedIn = i.HandedInDate.ToString()
});
public class Handin {
public int HandinId { get; set; }
public int StudentId { get; set; }
public int AssignmentId { get; set; }
public bool? Done { get; set; }
public bool? NeedHelp { get; set; }
[DisplayFormat(DataFormatString = "{0:dd/MM/yyyy}")]
public DateTime? HandedInDate { get; set; }
public virtual Student Student { get; set; }
public virtual Assignment Assignment { get; set; }
}

You need to join the two lists. You can do it with LINQ syntax like this:
var StudentsHandedInDatFeed =
from h in HandInData
join d in Distributions on h.AssignmentId equals d.AssignmentId
select new {
RealDeadline = d.Deadline,
Help = h.NeedHelp,
// etc
};
The join will only include values from HandInData where there is a matching value in Distributions, so this takes care of your Where(a => Distributions.Any(... code as well.

Where condition inside lambda expression c#

I have a entity like
public class Program
{
public int ID { get; set; }
public bool IsActive { get; set; }
public string Title { get; set; }
}
and
public class EMetrics
{
public int ID { get; set; }
public bool IsActive { get; set; }
public string Title { get; set; }
public List<Program> Programs { get; set; }
}
I have repository method like,
IEnumerable<EMetrics> IEmetricsRepository.GetAllByProgram(params int[] programIds)
{
var metrics = EntitySet
.Where(x => programIds.Contains(x.Programs.Select(x => x.ID)))
.ToList();
return metrics;
}
[The above code throwing build error]
Here only where I am facing problem to get the EMetrics based on the program Ids array params.
I want list Emetrics which are associated with the program.

You're incorrectly accessing the same input parameter in your LINQ. It should be refactored by changing your inner Select to use a different parameter:
IEnumerable<EMetrics> IEmetricsRepository.GetAllByProgram(params int[] programIds)
{
var metrics = EntitySet
.Where(x => programIds.Contains(x.Programs.Select(y => y.ID)))
.ToList();
return metrics;
}

So you want to check if all elements of one collection are present in the other. In LINQ that can be done with combination of Except and Any:
var metrics = EntitySet
.Where(x => x.Programs.Select(p => p.ID).Except(programIds).Any())
.ToList();
Fyi - your current code is failing because Array.Contains expects a single item, an int in this case, while you are giving it a whole enumerable