C# Collections & LINQ.

The containers a C# program reaches for and the query operators that read them. Covers 12 sub-skills.

• C# Collections & LINQ · 1 of 3

  Dictionaries & sets

  What does a set hold?

  Amembers, with all repeats keptBpairs, with no repeats keptCmembers, with no repeats keptDpairs, with all repeats kept

• C# Collections & LINQ · 2 of 3

  LINQ performance

  What does a chain pay each time it is walked?

  Athe last step, once onlyBevery step, once onlyCthe last step, over againDevery step, over again

• C# Collections & LINQ · 3 of 3

  Deferred execution

  A count is taken twice in one request and the numbers disagree. What does the measurement point at?

  using System.Linq;var nums = new List<int> { 1, 2 };var q = nums.Where(n => n > 0);Console.WriteLine(q.Count());nums.Add(3);Console.WriteLine(q.Count());

  Athe query changing between the walksBthe source changing between the buildsCthe source changing between the walksDthe query changing between the builds