LINQ - filter child collection

Question

I\'d like to be able to query parent entities and filter the contents of a child collection.

For example, I have a collection of OrderHeaders. I want to query this

Answer 1

Try the following:

var filtered = orders
    .Where(o => o.Detail.Any(d => d.StockCode == "STK2"))
    .Select(o => new { Order = o, Details = o.Detail.Where(d => d.StockCode == "STK2") });

Which is then useable like so:

foreach (var entity in filtered)
{
    Console.WriteLine("Account {0} ", entity.Order.AccountCode);
    foreach (var detail in entity.Details)
    {
        Console.WriteLine("StockCode {0}, Quantity {1}", detail.StockCode, detail.Quantity);
    }
    Console.WriteLine();
}