C# 0 The Complete Reference

PART I

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PART IPART I

    for(count = 0; count < 5; count = count+1)

      Console.WriteLine("This is count: " + count);

    Console.WriteLine("Done!");

  }

}

The output generated by the program is shown here:

This is count: 0

This is count: 1

This is count: 2

This is count: 3

This is count: 4

Done!

In this example, 

count

 is the loop control variable. It is set to zero in the initialization portion 

of the 

for

. At the start of each iteration (including the first one), the conditional test 

count < 5

is performed. If the outcome of this test is true, the 

WriteLine( )

 statement is executed. Next, 

the iteration portion of the loop is executed, which adds 1 to 

count

. This process continues 

until

count

 reaches 5. At this point, the conditional test becomes false, causing the loop to 

terminate. Execution picks up at the bottom of the loop.

As a point of interest, in professionally written C# programs you will almost never see 

the iteration portion of the loop written as shown in the preceding program. That is, you 

will seldom see statements like this:

count = count + 1;

The reason is that C# includes a special increment operator that performs this operation. 

The increment operator is 

++

 (that is, two consecutive plus signs). The increment operator 

increases its operand by one. By use of the increment operator, the preceding statement can 

be written like this:

count++;

Thus, the 

for

 in the preceding program will usually be written like this:

for(count = 0; count < 5; count++)

You might want to try this. As you will see, the loop still runs exactly the same as it did before.

C# also provides a decrement operator, which is specified as 

– –

. This operator decreases 

its operand by one.