C# 4 and .NET 4

72 ❘ ChaPTer 3 Objects And types
Method Overloading
C# supports method overloading — several versions of the method that have different signatures (that is,
the same name, but a different number of parameters and/or different parameter data types). To overload
methods, you simply declare the methods with the same name but different numbers or types of parameters:
class ResultDisplayer
{
void DisplayResult(string result)
{
// implementation
}
}
void DisplayResult(int result)
{
// implementation
}
If optional parameters won’t work for you, then you need to use method overloading to achieve the same effect:
class MyClass
{
int DoSomething(int x) // want 2nd parameter with default value 10
{
DoSomething(x, 10);
}
}
int DoSomething(int x, int y)
{
// implementation
}
As in any language, method overloading carries with it the potential for subtle runtime bugs if the wrong
overload is called. Chapter 4 discusses how to code defensively against these problems. For now, you should
know that C# does place some minimum restrictions on the parameters of overloaded methods:
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Properties
It is not sufficient for two methods to differ only in their return type.
It is not sufficient for two methods to differ only by virtue of a parameter having been declared as ref
or out.
The idea of a property is that it is a method or pair of methods that is dressed to look like a field. A good
example of this is the Height property of a Windows Form. Suppose that you have the following code:
// mainForm is of type System.Windows.Forms
mainForm.Height = 400;
On executing this code, the height of the window will be set to 400, and you will see the window resize
on the screen. Syntactically, this code looks like you’re setting a field, but in fact you are calling a property
accessor that contains code to resize the form.
To define a property in C#, you use the following syntax:
public string SomeProperty
{
get
{
return "This is the property value.";
}
set
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