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

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LESSON 24 InItIalIzIng Objects

Note that the object’s Dispose method is called even if the program exits from the block due to

an exception.

INVOKING OTHER CONSTRUCTORS

You can give a class many different constructors as long as they have different parameter lists (so

C# can tell them apart). For example, you might give the

Person class a parameterless constructor;

a second constructor that takes first name and last name as parameters; and a third constructor that

takes first and last name, street, city, state, and ZIP Code as parameters.

Often when you give a class multiple constructors, some of them perform the same actions. In the

Person example, the constructor that initializes first name, last name, street, city, state, and ZIP

Code probably does the same things that the second constructor does to initialize just first and last

name (plus more).

You can also find overlapping constructor functionality when one class inherits from another. For

example, suppose the

Person class has FirstName and LastName properties. The Employee class

inherits from

Person and adds some other properties such as EmployeeId and MailStop. The

Person class’s constructor initializes the FirstName and LastName properties, something that the

Employee class’s constructors should also do.

Having several methods perform the same tasks makes debugging and maintaining code harder.

Fortunately, C# provides a ...