Remove Duplicate item from list based on condition

Question

I have a class Items with properties ( Name, Price).

   Item1       $100
   Item2       $200
   Item3       $150
   Item1       $500
   Item3       $150

I want to remove items only if Name exists more than once and price is $500 using LINQ and without creating Custom comparer? for above one item1 with $500 will be removed from list.

Thanks,

Answer 1

Try this:

var result = items
    .GroupBy(item => item.Name)
    .SelectMany(g => g.Count() > 1 ? g.Where(x => x.Price != 500) : g);

First group by name. If the group has more than 1 item, select only items from the group where the price is not 500.

Answer 2

var result =
    from item in items
    where item.Price != 500 || items.Count(i => i.Name == item.Name) == 1
    select item;