в 15:31, 26 мая 2010

2010-05-26T15:31:53Z

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2010-05-26T12:17:27Z

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==Increment and Decrement==

<p>The ++ and the -- are the increment and decrement operators.</p>
<p>The increment operator adds 1 to its operand, and the decrement operator subtracts 1.</p>

<source lang="csharp">x = x + 1;</source>

==Operators ++==

<source lang="csharp">using System;
class Class1
{
[STAThread]
static void Main(string[] args)
{
MyCar car = 5;
for( int i = 0; i < 20; ++i )
{
car++;
Console.WriteLine( "{0}", car.GetSpeed());
}
}
}
public class MyCar
{
private static int speed = 2;
private const int maxSpeed = 200;

public bool ChangeSpeed(int newSpeed)
{
if( newSpeed > maxSpeed )
return false;
speed = newSpeed;
return true;
}
public static MyCar operator ++( MyCar car )
{
car.ChangeSpeed(++speed);
return car;
}
public static implicit operator MyCar( int from )
{
MyCar car = new MyCar();
car.ChangeSpeed( from );
return car;
}
public int GetSpeed()
{
return speed;
}
}</source>

==postfix decrement==

<source lang="csharp">class MainClass
{
public static void Main()
{
int length = 3;
int newLength = length--;
System.Console.WriteLine("Postfix decrement example");
System.Console.WriteLine("length = " + length);
System.Console.WriteLine("newLength = " + newLength);
}
}</source>
<pre class=codeResult>Postfix decrement example
length = 2
newLength = 3</pre>

==postfix increment==

<source lang="csharp">class MainClass
{
public static void Main()
{
int length = 3;
int newLength = length++;
System.Console.WriteLine("Postfix increment example");
System.Console.WriteLine("length = " + length);
System.Console.WriteLine("newLength = " + newLength);
}
}</source>
<pre class=codeResult>Postfix increment example
length = 4
newLength = 3</pre>

==Pre And Post Increment==

<source lang="csharp">using System;
class MainClass
{
static void Main()
{
int x = 5, y;
y = x++;
Console.WriteLine("y: {0}, x: {1}", y, x);
x = 5;
y = ++x;
Console.WriteLine("y: {0}, x: {1}", y, x);
x = 5;
y = x--;
Console.WriteLine("y: {0}, x: {1}", y, x);
x = 5;
y = --x;
Console.WriteLine("y: {0}, x: {1}", y, x);
}
}</source>
<pre class=codeResult>y: 5, x: 6
y: 6, x: 6
y: 5, x: 4
y: 4, x: 4</pre>

==prefix decrement==

<source lang="csharp">class MainClass
{
public static void Main()
{

int length = 3;
int newLength = --length;
System.Console.WriteLine("Prefix decrement example");
System.Console.WriteLine("length = " + length);
System.Console.WriteLine("newLength = " + newLength);
}
}</source>
<pre class=codeResult>Prefix decrement example
length = 2
newLength = 2</pre>

==prefix increment==

<source lang="csharp">class MainClass
{
public static void Main()
{
int length = 3;
int newLength = ++length;
System.Console.WriteLine("Prefix increment example");
System.Console.WriteLine("length = " + length);
System.Console.WriteLine("newLength = " + newLength);
}
}</source>
<pre class=codeResult>Prefix increment example
length = 4
newLength = 4</pre>

==The difference between prefix and postfix forms of ++==

<source lang="csharp">using System;

class Example {
public static void Main() {
int x, y;
int i;

x = 1;
Console.WriteLine("Series generated using y = x + x++;");
for(i = 0; i < 10; i++) {
y = x + x++; // postfix ++
Console.WriteLine(y + " ");
}
Console.WriteLine();

x = 1;
Console.WriteLine("Series generated using y = x + ++x;");
for(i = 0; i < 10; i++) {
y = x + ++x; // prefix ++
Console.WriteLine(y + " ");
}
Console.WriteLine();

}
}</source>
<pre class=codeResult>Series generated using y = x + x++;
2
4
6
8
10
12
14
16
18
20
Series generated using y = x + ++x;
3
5
7
9
11
13
15
17
19
21</pre>

==Using the Post-Increment Operator==

<source lang="csharp">class MainClass
{
static void Main()
{
int count;
int result;
count = 0;
result = count++;
System.Console.WriteLine("result = {0} and count = {1}",result, count);
}
}</source>

==Using the Pre-Increment Operator==

<source lang="csharp">class MainClass
{
static void Main()
{
int count;
int result;
count = 0;
result = ++count;
System.Console.WriteLine("result = {0} and count = {1}", result, count);
}
}</source>

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в 15:31, 26 мая 2010

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