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Building Query Expressions Using the Enumerable Type and

Anonymous Methods

Given that C# 2008 lambda expressions are simply shorthand notations for working with

anonymous methods, consider the third query expression created within the

QueryStringsWithAnonymousMethods() helper function:

static void QueryStringsWithAnonymousMethods()

{

Console.WriteLine("***** Using Anonymous Methods *****");

string[] currentVideoGames = {"Morrowind", "BioShock",

"Half Life 2: Episode 1", "The Darkness",

"Daxter", "System Shock 2"};

// Build the necessary Func<> delegates using anonymous methods.

Func searchFilter =

delegate(string game) { return game.Length > 6; };

Func itemToProcess = delegate(string s) { return s; };

// Pass the delegates into the methods of Enumerable.

var subset = currentVideoGames.Where(searchFilter)

.OrderBy(itemToProcess).Select(itemToProcess);

// Print out the results.

foreach (var game in subset)

Console.WriteLine("Item: {0}", game);

Console.WriteLine();

}

This iteration of the query expression is even more verbose, because we are manually creating

the Func<> delegates used by the Where(), OrderBy(), and Select() methods of the Enumerable type.

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On the plus side, the anonymous method syntax does keep all the processing contained within

a single method definition. Nevertheless, this method is functionally equivalent to the

QueryStringsWithEnumerableAndLambdas() and QueryStringsWithOperators() methods created

in the previous sections.