Question

I have the following Method

public static List<T> MergeAndSort<T>(List<List<T>> listOfLists) where T : Foo
    {
        List<T> list = listOfLists.SelectMany(bunch => bunch).ToList();

        list.OrderBy(x => x.FooLongMember);

        return list;
    }

I look for a solution that provides a completely generic version. Currently I need to specify what T is as well as specify the specific member name within Foo in order to order by such member. The member currently is of type long. Can I rewrite the function to at least not have to specify that I pass in a List of Lists of type Foo? I target C#, .Net4.0. Thanks

Answer 1

something like this?

public static IOrderedEnumerable<T> MergeSortWrapper<T,TKey>(
      IEnumerable<IEnumerable<T>> listOfLists,
      Func<T,TKey> keySelector) 
{
    return listOfLists.SelectMany(bunch => bunch)
                      .OrderBy(keySelector);
}

–

var result = MergeSortWrapper(listOfListOfFoos, x => x.FooLongMember).ToList();