The application must provide a component part list for any product. The component part list must give the quantity of
each distinct part that is required to manufacture that product.
You need to create a LINQ expression that delivers a a result of type IEnumerable<Tuple<int,Part>> to meet the requirements.
Which expression should you use?
A.
IEnumerable<Tuple<int, Part>> result = part.Children
.Distinct()
.GroupBy(p => p)
.Select(g => Tuple.Create(g.Count(), g.Key));
B.
IEnumerable<Tuple<int, Part>> result = part.Descendants
.GroupBy(p => p)
.Select(g => Tuple.Create(g.Count(), g.Key));
C.
IEnumerable<Tuple<int, Part>> result = part.Descendants
.ToDictionary(c => c)
.Select(d => Tuple.Create(d.Value.Children.Count(), d.Key));
D.
IEnumerable<Tuple<int, Part>> result = part.Children
.GroupBy(p => p)
.Select(g => Tuple.Create(g.Count(), g.Key));
E.
IEnumerable<Tuple<int, Part>> result = part.Descendants
.Distinct()
.GroupBy(p => p)
.Select(g => Tuple.Create(g.Count(), g.Key));
What is the difference between C and D? How could candidate know that parts are stored under “Descendants” collection and not under “Children”?
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Descendants is not a collection. It’s an XElement class dynamic property: http://msdn.microsoft.com/en-us/library/vstudio/bb943867(v=vs.100).aspx
No such class with a name ‘Children’ exists.
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sorry, i mean between B and D
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This one is part of a case study, that information is given there.
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Why doesn’t suggested answer use Distinct() method? Like E?
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Because Distinct would remove duplicate parts, and the question asks you to get their totals.
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