Practicing and exploring

Test your knowledge and understanding by answering some questions, get some hands-on practice, and explore, with deeper research into the topics covered in this chapter.

Exercise 9.1 – test your knowledge

Answer the following questions:

1. What are the two requirements to use LINQ?

2. Which LINQ extension method would you use to return a subset of properties from a type?

3. Which LINQ extension method would you use to filter a sequence?

4. List five LINQ extension methods that perform aggregation.

5. What is the difference between the Select and SelectMany extension methods?

Exercise 9.2 – practice querying with LINQ

Create a console application named Ch09_Exercise02 that prompts the user for a city and then lists the company names for Northwind customers in that city, as shown in the following output:

Enter the name of a city: London
There are 6 customers in London:
Around the Horn
B's Beverages
Consolidated Holdings
Eastern Connection
North/South
Seven Seas Imports

Enhance the application...