Book --> Visual C# How to Program (6th Edition)

1. Exercise 9.3 on page 392-393.

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b) c) The Remove method of the List class removes an element at a LINQ e Rmthod of the List class removes an element at a specific indesx. Answers to Self-Review Exercises 9.1 a) Count. b) where. c) Collections. d) Add. e) Distinct. 9.2 a) False. The descending modifier is used b) True. c) False. Remove removes the first element equal to its argument. Re is used to make orderby sort in descending order moveAt removes the el ement at a specific index. Exercises 9.3 (Querying an Array ofInvoice Objects) Use the class Invoice provided in the ex09 03 fold er with this chapter's examples to create an array of Invoice objects. Use the sample data shown in Fig. 9.8. Class Invoice includes four properties-a PartNumber (type int), a PartDescription (ype string), a Quantity of the item being purchased (type int) and a Price (type decimal). Perform the following queries on the array of Invoice objects and display the results a) Use LINQ to sort the Invoice objects by PartDescription. b) Use LINQ to sort the Invoice objects by Price. c) Use LINQ to select the PartDescription and Quantity and sort the resuls by Quantity. b) c) The Remove method of the List class removes an element at a LINQ e Rmthod of the List class removes an element at a specific indesx. Answers to Self-Review Exercises 9.1 a) Count. b) where. c) Collections. d) Add. e) Distinct. 9.2 a) False. The descending modifier is used b) True. c) False. Remove removes the first element equal to its argument. Re is used to make orderby sort in descending order moveAt removes the el ement at a specific index. Exercises 9.3 (Querying an Array ofInvoice Objects) Use the class Invoice provided in the ex09 03 fold er with this chapter's examples to create an array of Invoice objects. Use the sample data shown in Fig. 9.8. Class Invoice includes four properties-a PartNumber (type int), a PartDescription (ype string), a Quantity of the item being purchased (type int) and a Price (type decimal). Perform the following queries on the array of Invoice objects and display the results a) Use LINQ to sort the Invoice objects by PartDescription. b) Use LINQ to sort the Invoice objects by Price. c) Use LINQ to select the PartDescription and Quantity and sort the resuls by Quantity