C# 5.0 Programmer's Reference

Exercises ❘ 315
private ConsoleTyes Console { get; set; }
}
// Display the Person's name.
public void ShowName()
{
Console.WriteLine(Name);
}
The intent is for the Console property to store the player’s console type. Unfortunately, when the
compiler sees Console in the ShowName method, it finds the property, not the class, that displays
messages in the Console window.
If you place global:: in front of a namespace, the compiler begins searching for the symbol in the
global namespace instead of looking for it locally. That means you can use the following statement
to correctly find the Console.WriteLine method.
global::System.Console.WriteLine(Name);
Usually it is better to avoid names that conflict with the system namespaces. For example, if you
change the property’s name to ConsoleType, there’s no confusion.
Summary
Namespaces are everywhere in C#. Every piece of code you write is contained in some namespace,
even if it is only the application’s root namespace. Despite the pervasiveness of namespaces, many
developers never need to use them explicitly, so they find them somewhat mystifying.
Namespaces are quite simple. They merely divide programming items into a hierarchy to prevent name
collisions, and they enable you to group related items.
The using directive lets a program refer to items in a namespace without using fully qualified
names. The using directive can also define an alias for a namespace, so you can refer to it by using
a short abbreviation. This is particularly useful for resolving names that appear in more than one
of the namespaces that your program uses.
The .NET Framework contains hundreds of namespaces, some of which are more useful than
others. The next chapter describes classes that are in two of the most useful namespaces: System
.Collections and System.Collections.Generic. The classes in those namespaces let you arrange
and manage objects in particularly useful ways such as in stacks, queues, lists, and dictionaries.
Exercises
1. Suppose you are writing a program that uses the System.Security.Cryptography
.SHA512Managed class but you (understandably) don’t want to type all that out. Give two
methods for shortening this in your code. What are the advantages and disadvantages of each
2. Suppose your program needs to use the System.Windows.Controls.Calendar control
and the System.Globalization.Calendar class. Give three methods for differentiating
between the two classes in your code. What are the advantages and disadvantages of each
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