Stephens' C# Programming with Visual Studio® 2010 24-Hour Trainer

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LESSON 37 LINQ to objects

ORDER BY CLAUSES

Often the result of a query is easier to read if you sort the selected values. You can do this by inserting

an order by clause between the where clause and the select clause.

The order by clause begins with the keyword

orderby followed by one or more values separated by

commas that determine how the results are ordered.

Optionally you can follow a value by the keyword

ascending (the default) or descending to determine

whether the results are ordered in ascending (1-2-3 or A-B-C) or descending (3-2-1 or C-B-A) order.

For example, the following query selects

Customers with negative balances and orders them so

those with the smallest (most negative) values come first:

var negativeQuery =

from Customer cust in customers

where cust.Balance < 0

orderby cust.Balance ascending

select cust;

The following version orders the results first by balance and then, if two customers have the same

balance, by last name:

var negativeQuery =

from Customer cust in customers

where cust.Balance < 0

orderby cust.Balance, cust.LastName

select cust;

SELECT CLAUSES

The select clause determines what data is pulled from the data source and stored in the result. All of

the previous examples select the data over which they are ranging. For example, the FindCustomers

example program ranges over an array of

Customer objects and selects certain Customer objects.

Instead of sele ...