C# 0 The Complete Reference

int

. Thus, the preceding statement declares a variable called 

x

 of type 

int

.

The next line declares a second variable called 

y

.

int y; // this declares another variable

Notice that it uses the same format as the first except that the name of the variable is 

different.

In general, to declare a variable, you will use a statement like this:

type var-name

;

Here, 

type

 specifies the type of variable being declared, and 

var-name

is the name of the 

variable. In addition to 

int

, C# supports several other data types.

The following line of code assigns 

x

 the value 

100

:

x = 100; // this assigns 100 to x

In C#, the assignment operator is the single equal sign. It copies the value on its right side 

into the variable on its left.

The next line of code outputs the value of 

x

 preceded by the string “x contains ”.

Console.WriteLine("x contains " + x);

In this statement, the plus sign causes the value of 

x

 to be displayed after the string that 

precedes it. This approach can be generalized. Using the 

+

 operator, you can chain together 

as many items as you want within a single 

WriteLine

(

 )

 statement.

The next line of code assigns 

y

the value of 

x

 divided by 

2

:

y = x / 2;

This line divides the value in 

x

 by 

2

 and then stores that result in 

y

. Thus, after the line 

executes,

y

 will contain the value 50. The value of 

x

 will be unchanged. Like most other 

computer languages, C# supports a full range of arithmetic operators, including those 

shown here:

+

Addition

–

Subtraction

*

Multiplication

/

Division

Here are the next two lines in the program:

Console.Write("y contains x / 2: ");

Console.WriteLine(y);

Two new things are occurring here. First, the built-in method 

Write( )

 is used to display the 

string “y contains x / 2: ”. This string is 

not

 followed by a new line. This means that when 

the next output is generated, it will start on the same line. The 

Write( )

 method is just like 

WriteLine( )

, except that it does not output a new line after each call. Second, in the call 

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