This print for content only-size & color not accurate 7" X 9-1/4" / casebound / malloy

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foreach (Car c in onlyBMWs)

{

Console.WriteLine(c.ToString());

}

}

As seen earlier in this chapter, when you are building a where clause, it is permissible to make

use of any valid C# operators to build complex expressions. For example, consider the following

query that only extracts out the BMWs going at least 100 mph:

// Get BMWs going at least 100 mph.

var onlyFastBMWs = from c in myCars

where c.Make == "BMW" && c.Speed >= 100

select c;

foreach (Car c in onlyFastBMWs)

{

Console.WriteLine("{0} is going {1} MPH", c.PetName, c.Speed);

}

Projecting New Data Types

It is also possible to project new forms of data from an existing data source. Let’s assume that you

wish to take the incoming Car[] parameter and obtain a result set that accounts only for the make

and color of each vehicle. To do so, you can define a select statement that dynamically yields new

types via C# 2008 

anonymous types. Recall from Chapter 13 that the compiler defines a read-only

property and a read-only backing field for each specified name, and also is kind enough to override

ToString(), GetHashCode(), and Equals():

var makesColors = from c in myCars select new {c.Make, c.Color};

foreach (var o in makesColors)

{

// Could also use Make and Color properties directly.

Console.WriteLine(o.ToString());

}

Figure 14-8 shows the output of each of these new queries.

Figure 14-8.

Enumerating over subsets

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Reversing Result Sets

You can reverse the items within a result set quite simply using the generic Reverse() method of

the Enumerable type. For example, the following method selects all items from the incoming Car[]

parameter in reverse:

static void ReversedSelection(Car[] myCars)

{