include property from derived class EF

Question

case: i have a list of Companies, each Company contains one Store and some other properties like address, name, .... A store can be of type FruitStore or of type VegetableStore (both are derived from Store). If the store is a fruitstore i want to include a property that is unique for fruitstore for example TheBestOrange (wich is an object).

how do i include theBestOrange in my query and also the properties from company?

I have

companies.Include(s => s.Store)
         .OfType<FruitStore>()
         .Include(a => a.theBestOrange)

but this changes my return type to a list of fruitstores instead of a list of companies

i hope i made myself clear.

Answer 1

I'm assuming you want to include all stores in your query, not just fruit stores. You can't project to a list of objects where some of the objects include a property and others don't, since they would be different types. So it will have to be a nullable property. Maybe something like this (untested):

var query = companies.Select(c => new { 
    CompanyProp1 = c.CompanyProp1, 
    CompanyProp2 = c.CompanyProp2, 
    StoreProp1 = c.Store.StoreProp1,
    TheBestOrange = c.Store is FruitStore ? ((FruitStore)c.Store).theBestOrange : null
});