Entity Framework - How to pass Include off to method caller? - entity-framework

Question

I have a method that calls a DbSet from an Entity Framework database:
public static List<CostEntryVM> ToViewModelList(this DbSet<CostEntry> CostEntrys, Expression<Func<CostEntry, bool>> query) {
return AutoMapper.Mapper.Map<List<CostEntry>, List<CostEntryVM>>(
CostEntrys
.Include(x => x.Job)
.Include(x => x.User)
.Where(query)
.ToList());
}
To use this I can then do for example:
CostEntrys.ToViewModelList(x => x.Active == true);
I want to also be able to call:
CostEntrys.ToViewModelList(x => x.Include(y => y.Job).Include(y.User), x => x.Active == true);
I can't for the life of me figure out how the method signature should look or how I would then apply that to the DbSet.
How can I do this?

Answer 1

First you need to change the extension method to:
public static List<CostEntryVM> ToViewModelList(
this DbSet<CostEntry> CostEntrys,
Expression<Func<CostEntry, bool>> query,
Func<IQueryable<CostEntry>, IQueryable<CostEntry>> func)
{
// Adding the predicate query
IQueryable<CostEntry> queryable = CostEntrys.Where(query);
// Adding include paths
IQueryable<CostEntry> queryableWithFetch = func(queryable);
// Executing the query and map it to the view model object
return AutoMapper.Mapper.Map<List<CostEntry>, List<CostEntryVM>>(
queryableWithFetch.ToList());
}
And then you can call it:
CostEntrys.ToViewModelList(
x => x.Active == true,
x => x.Include(y => y.Job).Include(y.User));