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==control the operator evaluation sequence==

<source lang="csharp">
using System;
public class MainClass {
static void Main(string[] args) {
int a;
a = -42;
Console.WriteLine("{0}", a);
int b = 2;
int c = 42;
a = b * (-c);
Console.WriteLine("{0}", a);
c = -42;
a = b * (+c);
Console.WriteLine("{0}", a);
}
}
</source>

==Demonstrates compound assignment operators==

<source lang="csharp">
/*
C# Programming Tips & Techniques
by Charles Wright, Kris Jamsa
Publisher: Osborne/McGraw-Hill (December 28, 2001)
ISBN: 0072193794
*/
//
// Assign.cs - Demonstrates compound assignment operators
//
// Compile this program with the following command line:
// C:>csc Assign.cs
//
namespace nsAssignment
{
using System;

public class Assign
{
static public void Main ()
{
unsafe
{
int x = sizeof (decimal);
Console.WriteLine ("sizeof decimial = " + x);
}
//
// Start with an integer variable
int Var = 2;
//
// Show the starting value
Console.WriteLine ("At the beginning, Var = {0}", Var);
//
// Multiply the variable by something
Var *= 12;
Console.WriteLine ("After Var *= 12, Var = {0}", Var);
//
// Add something to the variable
Var += 42;
Console.WriteLine ("After Var += 42, Var = {0}", Var);
//
// Divide the variable by something
Var /= 6;
Console.WriteLine ("After Var /= 6, Var = {0}", Var);
//
// Shift the bits in the variable four spaces to the left
// This is the same as multiplying by 16 (2 to the fourth power)
Var <<= 4;
Console.WriteLine ("After Var <<= 4, Var = {0}", Var);
//
// Shift the bits in the variable four spaces to the right using
// and expression on the right. This is the same as dividing
// by 16.
int Shift = 3;
Var >>= Shift + 1;
Console.WriteLine ("After Var >>= Shift + 1, Var = {0}", Var);
//
// Modulo divide the variable by something
Var %= 6;
Console.WriteLine ("After Var %= 6, Var = {0}", Var);
}
}
}

</source>

==Demonstrate the difference between prefix postfix forms of ++==

<source lang="csharp">
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
/*
Demonstrate the difference between prefix
postfix forms of ++.
*/
using System;

public class PrePostDemo {
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>

==Demonstrate the relational and logical operators==

<source lang="csharp">
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Demonstrate the relational and logical operators.

using System;

public class RelLogOps {
public static void Main() {
int i, j;
bool b1, b2;

i = 10;
j = 11;
if(i < j) Console.WriteLine("i < j");
if(i <= j) Console.WriteLine("i <= j");
if(i != j) Console.WriteLine("i != j");
if(i == j) Console.WriteLine("this won"t execute");
if(i >= j) Console.WriteLine("this won"t execute");
if(i > j) Console.WriteLine("this won"t execute");

b1 = true;
b2 = false;
if(b1 & b2) Console.WriteLine("this won"t execute");
if(!(b1 & b2)) Console.WriteLine("!(b1 & b2) is true");
if(b1 | b2) Console.WriteLine("b1 | b2 is true");
if(b1 ^ b2) Console.WriteLine("b1 ^ b2 is true");
}
}

</source>

==Demonstrate the short-circuit operators==

<source lang="csharp">
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Demonstrate the short-circuit operators.

using System;

public class SCops {
public static void Main() {
int n, d;

n = 10;
d = 2;
if(d != 0 && (n % d) == 0)
Console.WriteLine(d + " is a factor of " + n);

d = 0; // now, set d to zero

// Since d is zero, the second operand is not evaluated.
if(d != 0 && (n % d) == 0)
Console.WriteLine(d + " is a factor of " + n);

/* Now, try the same thing without short-circuit operator.
This will cause a divide-by-zero error. */
if(d != 0 & (n % d) == 0)
Console.WriteLine(d + " is a factor of " + n);
}
}

</source>

==Illustrates the use of the arithmetic operators==

<source lang="csharp">
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example3_2.csc illustrates the use of
the arithmetic operators
*/
public class Example3_2
{
public static void Main()
{
// integers and arithmetic operators
System.Console.WriteLine("10 / 3 = " + 10 / 3);
System.Console.WriteLine("10 % 3 = " + 10 % 3);
int intValue1 = 10;
int intValue2 = 3;
System.Console.WriteLine("intValue1 / intValue2 = " +
intValue1 / intValue2);
System.Console.WriteLine("intValue1 % intValue2 = " +
intValue1 % intValue2);
// floats and arithmetic operators
System.Console.WriteLine("10f / 3f = " + 10f / 3f);
float floatValue1 = 10f;
float floatValue2 = 3f;
System.Console.WriteLine("floatValue1 / floatValue2 = " +
floatValue1 / floatValue2);
// doubles and arithmetic operators
System.Console.WriteLine("10d / 3d = " + 10d / 3d);
System.Console.WriteLine("10.0 / 3.0 = " + 10.0 / 3.0);
double doubleValue1 = 10;
double doubleValue2 = 3;
System.Console.WriteLine("doubleValue1 / doubleValue2 = " +
doubleValue1 / doubleValue2);
// decimals and arithmetic operators
System.Console.WriteLine("10m / 3m = " + 10m / 3m);
decimal decimalValue1 = 10;
decimal decimalValue2 = 3;
System.Console.WriteLine("decimalValue1 / decimalValue2 = " +
decimalValue1 / decimalValue2);
// multiple arithmetic operators
System.Console.WriteLine("3 * 4 / 2 = " + 3 * 4 / 2);
}
}

</source>

==Illustrates the use of the bitwise operators==

<source lang="csharp">
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example3_6.cs illustrates the use of
the bitwise operators
*/
public class Example3_6
{
public static void Main()
{
byte byte1 = 0x9a; // binary 10011010, decimal 154
byte byte2 = 0xdb; // binary 11011011, decimal 219
byte result;
System.Console.WriteLine("byte1 = " + byte1);
System.Console.WriteLine("byte2 = " + byte2);
// bitwise AND
result = (byte) (byte1 & byte2);
System.Console.WriteLine("byte1 & byte2 = " + result);
// bitwise OR
result = (byte) (byte1 | byte2);
System.Console.WriteLine("byte1 | byte2 = " + result);
// bitwise exclusive OR
result = (byte) (byte1 ^ byte2);
System.Console.WriteLine("byte1 ^ byte2 = " + result);
// bitwise NOT
result = (byte) ~byte1;
System.Console.WriteLine("~byte1 = " + result);

// left shift
result = (byte) (byte1 << 1);
System.Console.WriteLine("byte1 << 1 = " + result);
// right shift
result = (byte) (byte1 >> 1);
System.Console.WriteLine("byte1 >> 1 = " + result);
}
}

</source>

==Illustrates the use of the Boolean logical operators==

<source lang="csharp">
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example3_4.cs illustrates the use of
the Boolean logical operators
*/
public class Example3_4
{
public static void Main()
{
bool result;
// use of the Boolean logical AND operator
result = (1 == 1) && (2 > 1);
System.Console.WriteLine("(1 == 1) && (2 > 1) is " + result);
result = (1 == 1) && (2 < 1);
System.Console.WriteLine("(1 == 1) && (2 < 1) is " + result);
// use of the Boolean logical OR operator
result = (1 == 1) || (1 == 0);
System.Console.WriteLine("(1 == 1) || (1 == 0) is " + result);
result = (1 == 0) || (1 == 0);
System.Console.WriteLine("(1 == 0) || (1 == 0) is " + result);
// use of the Boolean logical NOT operator
result = !(1 == 0);
System.Console.WriteLine("!(1 == 0) is " + result);
result = !(1 == 1);
System.Console.WriteLine("!(1 == 1) is " + result);
}
}

</source>

==Illustrates the use of the comparison operators==

<source lang="csharp">
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example3_3.cs illustrates the use of
the comparison operators
*/
public class Example3_3
{
public static void Main()
{
bool result;
// false expressions
result = 10 == 1;
System.Console.WriteLine("10 == 1 is " + result);
result = 10 < 1;
System.Console.WriteLine("10 < 1 is " + result);
result = 10 <= 1;
System.Console.WriteLine("10 <= 1 is " + result);
// true expressions
result = 10 != 1;
System.Console.WriteLine("10 != 1 is " + result);
result = 10 > 1;
System.Console.WriteLine("10 > 1 is " + result);
result = 10 >= 1;
System.Console.WriteLine("10 >= 1 is " + result);
int intValue1 = 10;
int intValue2 = 1;
result = intValue1 != intValue2;
System.Console.WriteLine("intValue1 != intValue2 is " + result);
}
}

</source>

==Illustrates the use of the shortcut operators==

<source lang="csharp">
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example3_7.cs illustrates the use of
the shortcut operators
*/
public class Example3_7
{
public static void Main()
{
int length = 1;
length += 10;
System.Console.WriteLine("length = " + length);
length *= 2; // multiplies length by 2
System.Console.WriteLine("length = " + length);
length /= 3; // divides length by 3
System.Console.WriteLine("length = " + length);
}
}

</source>

==Illustrates the use of the ternary operator==

<source lang="csharp">
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example3_5.cs illustrates the use of
the ternary operator
*/
public class Example3_5
{
public static void Main()
{
int result;
result = 10 > 1 ? 20 : 10;
System.Console.WriteLine("result = " + result);
result = 10 < 1 ? 20 : 10;
System.Console.WriteLine("result = " + result);
}
}

</source>

==Math Operators with int value==

<source lang="csharp">
using System;
class Operators {
static void Main() {
int a, b, c, d, e;
a = 14;
b = 15;
c = 20;
d = a + b - c; //d=9
c += d; //c=29
e = c + d; //e=38
e /= 2; //e=19
Console.WriteLine("{0}", e);
}
}
</source>

==Numeric Operators 1==

<source lang="csharp">
/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
* Version: 1
*/
using System;
namespace Client.Chapter_2___Operators_and_Excpressions
{
public class NumericOperators1
{
static void Main(string[] args)
{
int a, b, c, d, e;
a = 1;
a += 1;
b = a;
b -= 2;
c = b;
c *= 3;
d = 4;
d /= 2;
e = 23;
e %= 3;
}
}
}

</source>

==Numeric Operators 3==

<source lang="csharp">
/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
* Version: 1
*/
using System;
namespace Client.Chapter_2___Operators_and_Excpressions
{
public class NumericOperators2
{
static void Main(string[] args)
{
int a,b,c,d,e,f;
a = 1; //1
b = a + 1; //2
b = b - 1; //1
c = 1; d = 2;
++c; //2
--d; //1
e = --c; // e = 1 c = 1
f = c--; // f = 1 c = 0
}
}
}

</source>

==Operator precedence==

<source lang="csharp">
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example3_10.cs illustrates operator precedence
*/
public class Example3_10
{
public static void Main()
{
int myInt = 2 + 5 * 10;
System.Console.WriteLine("2 + 5 * 10 = " + myInt);
myInt = (2 + 5) * 10;
System.Console.WriteLine("(2 + 5) * 10 = " + myInt);
myInt = 2 * 20 / 5;
System.Console.WriteLine("2 * 20 / 5 = " + myInt);
}
}

</source>

==Prefix and postfix versions of the increment and decrement operators==

<source lang="csharp">
/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
Example3_8.cs illustrates the use of
prefix and postfix versions of the
increment and decrement operators
*/
public class Example3_8
{
public static void Main()
{
// postfix increment
int length = 3;
int newLength = length++;
System.Console.WriteLine("Postfix increment example");
System.Console.WriteLine("length = " + length);
System.Console.WriteLine("newLength = " + newLength);
// prefix increment
length = 3;
newLength = ++length;
System.Console.WriteLine("Prefix increment example");
System.Console.WriteLine("length = " + length);
System.Console.WriteLine("newLength = " + newLength);
// postfix decrement
length = 3;
newLength = length--;
System.Console.WriteLine("Postfix decrement example");
System.Console.WriteLine("length = " + length);
System.Console.WriteLine("newLength = " + newLength);
// prefix decrement
length = 3;
newLength = --length;
System.Console.WriteLine("Prefix decrement example");
System.Console.WriteLine("length = " + length);
System.Console.WriteLine("newLength = " + newLength);
}
}

</source>

==Prevent a division by zero using the ? 1==

<source lang="csharp">
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Prevent a division by zero using the ?.
using System;

public class NoZeroDiv {
public static void Main() {
int result;
int i;

for(i = -5; i < 6; i++) {
result = i != 0 ? 100 / i : 0;
if(i != 0)
Console.WriteLine("100 / " + i + " is " + result);
}
}
}

</source>

==Relational Operators==

<source lang="csharp">
/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
*/
using System;
namespace Client.Chapter_2___Common_Type_System
{
public class RelationalOperators
{
static void Main(string[] args)
{
int a, b;
a = 1;
b = 2;
if (a > b)
b = 10;
if (b < a)
a = 10;
if (a >= b)
b = 20;
if (b <= a)
a = 20;
if (a == b)
b = 5;
if (b != a)
b = a;
}
}
}

</source>

==Relational Operators 3==

<source lang="csharp">
/*
* C# Programmers Pocket Consultant
* Author: Gregory S. MacBeth
* Email: gmacbeth@comporium.net
* Create Date: June 27, 2003
* Last Modified Date:
*/
using System;
namespace Client.Chapter_2___Operators_and_Excpressions
{
public class RelationalOperators2
{
static void Main(string[] args)
{
int a = 10, b = 20, c = 30;
if (a < 15 && b < 20)
c = 10;
if (a < 15 || b < 20)
c = 15;
if (!(a == 15))
c = 25;
}
}
}

</source>

==Self decrease==

<source lang="csharp">
/*
Learning C#
by Jesse Liberty
Publisher: O"Reilly
ISBN: 0596003765
*/
using System;
public class SelfMiValues
{
static void Main()
{
int original = 10;
int result;
// increment then assign
result = --original;
Console.WriteLine("After prefix: {0}, {1}", original,
result);
// assign then increment
result = original--;
Console.WriteLine("After postfix: {0}, {1}",
original, result);
}
}

</source>

==Self increment==

<source lang="csharp">
/*
Learning C#
by Jesse Liberty
Publisher: O"Reilly
ISBN: 0596003765
*/
using System;
public class SelfValues
{
static void Main()
{
int original = 10;
int result;
// increment then assign
result = ++original;
Console.WriteLine("After prefix: {0}, {1}", original,
result);
// assign then increment
result = original++;
Console.WriteLine("After postfix: {0}, {1}",
original, result);
}
}

</source>

==Side-effects can be important==

<source lang="csharp">
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Side-effects can be important.

using System;

public class SideEffects {
public static void Main() {
int i;

i = 0;

/* Here, i is still incremented even though
the if statement fails. */
if(false & (++i < 100))
Console.WriteLine("this won"t be displayed");
Console.WriteLine("if statement executed: " + i); // displays 1

/* In this case, i is not incremented because
the short-circuit operator skips the increment. */
if(false && (++i < 100))
Console.WriteLine("this won"t be displayed");
Console.WriteLine("if statement executed: " + i); // still 1 !!
}
}

</source>

==Ternary operator==

<source lang="csharp">
/*
Learning C#
by Jesse Liberty
Publisher: O"Reilly
ISBN: 0596003765
*/
using System;
public class ThreeInputValues
{
static void Main()
{
int valueOne = 10;
int valueTwo = 20;
int maxValue = valueOne > valueTwo ? valueOne : valueTwo;
Console.WriteLine("ValueOne: {0}, valueTwo: {1}, maxValue: {2}",
valueOne, valueTwo, maxValue);
}
}

</source>

==The + Operator Is Left Associative==

<source lang="csharp">

using System;
public class MainClass {
public static void Main() {
Console.WriteLine(10 + 25 + "A"); // Same as (10 + 25) + "A", that is "35A"
Console.WriteLine("A" + 10 + 25); // Same as ("A" + 10) + 25, that is "A1025"
}
}
</source>

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в 15:31, 26 мая 2010

Admin: 1 версия