C# 0 The Complete Reference

PART I

C h a p t e r   6 :  

I n t r o d u c i n g   C l a s s e s   a n d   O b j e c t s  

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PART IPART I

      else Console.WriteLine(i + " is not prime.");

  }

}

Here is the output produced by the program:

2 is prime.

3 is prime.

4 is not prime.

5 is prime.

6 is not prime.

7 is prime.

8 is not prime.

9 is not prime.

In the program, 

IsPrime( )

 is called nine times, and each time a different value is passed. 

Let’s look at this process closely. First, notice how 

IsPrime( )

 is called. The argument is 

specified between the parentheses. When 

IsPrime( )

 is called the first time, it is passed value 

1. Thus, when 

IsPrime( )

 begins executing, the parameter 

x

 receives the value 1. In the 

second call, 2 is the argument, and 

x

 then has the value 2. In the third call, the argument 

is 3, which is the value that 

x

 receives, and so on. The point is that the value passed as an 

argument when 

IsPrime( )

 is called is the value received by its parameter, 

x

.

A method can have more than one parameter. Simply declare each parameter, separating 

one from the next with a comma. For example, here the 

ChkNum

 class is expanded by 

adding a method called