Question

i am facing problem with the return type for this function and not really getting anywhere near solving can someone help me with this?

here goes the function,

public IQueryable<System.Collections.Generic.Dictionary<discussion_category, List<discussion_board>>> GetDiscussion_categoriesWithBoards()
{
    return GetDiscussion_categories().Select(c =>
        new
        {
            Category = c,
            Boards = GetDiscussion_boardsByCategory(c.ID).ToList()
        }).ToDictionary(i => i.Category, i => i.Boards.ToList());
}

this is the other function that works which is used in the above function that doen’t work,

public IQueryable<discussion_board> GetDiscussion_boardsByCategory(int CategoryID)
{
    return this.ObjectContext.discussion_boards.Where(e => e.CategoryID == CategoryID);
}
public IQueryable<discussion_category> GetDiscussion_categories()
{
    return this.ObjectContext.discussion_categories;
}

I need this to be the return type:

IQueryable<System.Collections.Generic.Dictionary<discussion_category, List<discussion_board>>>

thank you friends!

Answer 1

Since you’re calling ToDictionary(), your method returns a Dictionary<>, not an IQueryable<>:

public Dictionary<discussion_category, List<discussion_board>>
GetDiscussion_categoriesWithBoards()
{
    // ...
}

If you absolutely want to return an IQueryable<> you can write something like:

public IQueryable<Dictionary<discussion_category, List<discussion_board>>>
GetDiscussion_categoriesWithBoards()
{
    return new[] {
        GetDiscussion_categories().Select(c => new {
            Category = c,
            Boards = GetDiscussion_boardsByCategory(c.ID).ToList()
        }).ToDictionary(i => i.Category, i => i.Boards.ToList())
    }.AsQueryable();
}