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

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

Func searchFilter = new Func(Filter);

Func itemToProcess = new Func(ProcessItem);

// 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();

}

// Delegate targets.

public static bool Filter(string s) {return s.Length > 6;}

public static string ProcessItem(string s) { return s; }

}

We can test this iteration of our string processing logic by calling this method within Main()

method of the Program class as follows:

VeryComplexQueryExpression.QueryStringsWithRawDelegates();

If you were to now run the application to test each possible approach, it should not be too sur-

prising that the output is identical regardless of the path taken. Keep the following points in mind

regarding how LINQ query expressions are represented under the covers:

• Query expressions are created using various C# query operators.

• Query operators are simply shorthand notations for invoking extension methods defined by

the System.Linq.Enumerable type.

• Many methods of Enumerable require delegates (Func<> in particular) as parameters.

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• Under C# 2008, any method requiring a delegate parameter can instead be passed a lambda

expression.

• Lambda expressions are simply anonymous methods in disguise (which greatly improve

readability).

• Anonymous methods are shorthand notations for allocating a raw delegate and manually

building a delegate target method.

Whew! That might have been a bit deeper under the hood than you wish to have gone, but I

hope this discussion has helped you understand what the user-friendly C# query operators are

actually doing behind the scenes. Let’s now turn our attention to the operators themselves.