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using System;

namespace OperatorsAppl
{
    class Program
    {
        static void Main(string[] args)
        {
            int a = 52;
            int b = 20;
            int c;

            c = a + b;
            Console.WriteLine("Line 1 - Value of c is {0}", c);
            c = a - b;
            Console.WriteLine("Line 2 - Value of c is {0}", c);
            c = a * b;
            Console.WriteLine("Line 3 - Value of c is {0}", c);
            c = a / b;
            Console.WriteLine("Line 4 - Value of c is {0}", c);
            c = a % b;
            Console.WriteLine("Line 5 - Value of c is {0}", c);
            c = a++;
            Console.WriteLine("Line 6 - Value of c is {0}", c);
            c = a--;
            Console.WriteLine("Line 7 - Value of c is {0}", c);
            Console.ReadLine();
        }
    }
}

Line 1 - Value of c is 72
Line 2 - Value of c is 32
Line 3 - Value of c is 1040
Line 4 - Value of c is 5
Line 5 - Value of c is 6
Line 6 - Value of c is 53
Line 7 - Value of c is 51

using System;

class Program
{
  static void Main(string[] args)
  {
      int a = 52;
      int b = 20;
      
      if (a == b)
      {
          Console.WriteLine("Line 1 - a is equal to b");
      }
      else
      {
          Console.WriteLine("Line 1 - a is not equal to b");
      }
      if (a < b)
      {
          Console.WriteLine("Line 2 - a is less than b");
      }
      else
      {
          Console.WriteLine("Line 2 - a is not less than b");
      }
      if (a > b)
      {
          Console.WriteLine("Line 3 - a is greater than b");
      }
      else
      {
          Console.WriteLine("Line 3 - a is not greater than b");
      }
      /* Lets change value of a and b */
      a = 5;
      b = 28;
      if (a <= b)
      {
         Console.WriteLine("Line 4 - a is either less than or equal to  b");
      }
      if (b >= a)
      {
         Console.WriteLine("Line 5-b is either greater than or equal to b");
      }
  }
}

Line 1 - a is not equal to b
Line 2 - a is not less than b
Line 3 - a is greater than b
Line 4 - a is either less than or equal to b
Line 5 - b is either greater than or equal to b

using System;

namespace OperatorsAppl
{
    class Program
    {
        static void Main(string[] args)
        {
            bool a = true;
            bool b = true;
           
            if (a && b)
            {
               Console.WriteLine("Line 1 - Condition is true");
            }
            if (a || b)
            {
                Console.WriteLine("Line 2 - Condition is true");
            }
            /* lets change the value of  a and b */
            a = false;
            b = true;
            if (a && b)
            {
                Console.WriteLine("Line 3 - Condition is true");
            }
            else
            {
                Console.WriteLine("Line 3 - Condition is not true");
            }
            if (!(a && b))
            {
                Console.WriteLine("Line 4 - Condition is true");
            }
            Console.ReadLine();
        }
    }
}

The above code will result in the following:

Line 1 - Condition is true
Line 2 - Condition is true
Line 3 - Condition is not true
Line 4 - Condition is true

Bitwise Operators

Bitwise operator works on bits and perform bit by bit operation. The truth tables for &, |, and ^ are as follows:

p	q	p & q	p | q	p ^ q
0	0	0	0	0
0	1	0	1	1
1	1	1	1	0
1	0	0	1	1

Assume if A = 60; and B = 13; now in binary format they will be as follows:

A = 0011 1100

B = 0000 1101

-----------------

A&B = 0000 1100

A|B = 0011 1101

A^B = 0011 0001

~A  = 1100 0011

The Bitwise operators supported by C# are listed in the following table. Assume variable A holds 60 and variable B holds 13 then:

Operator	Description	Example
&	Binary AND Operator copies a bit to the result if it exists in both operands.	(A & B) will give 12. which is 0000 1100
|	Binary OR Operator copies a bit if it exists in either operand.	(A | B) will give 61, which is 0011 1101
^	Binary XOR Operator copies the bit if it is set in one operand but not both.	(A ^ B) will give 49, which is 0011 0001
~	Binary Ones Complement Operator is unary and has the effect of 'flipping' bits.	(~A ) will give -61, which is 1100 0011 in 2's complement due to a signed binary number.
<<	Binary Left Shift Operator. The left operands value is moved left by the number of bits specified by the right operand.	A << 2 will give 240, which is 1111 0000
>>	Binary Right Shift Operator. The left operands value is moved right by the number of bits specified by the right operand.	A >> 2 will give 15, which is 0000 1111

Assignment Operators

There are following assignment operators supported by C#:

Operator	Description	Example
=	Simple assignment operator, Assigns values from right side operands to left side operand	C = A + B will assign value of A + B into C
+=	Add AND assignment operator, It adds right operand to the left operand and assign the result to left operand	C += A is equivalent to C = C + A
-=	Subtract AND assignment operator, It subtracts right operand from the left operand and assign the result to left operand	C -= A is equivalent to C = C - A
*=	Multiply AND assignment operator, It multiplies right operand with the left operand and assign the result to left operand	C *= A is equivalent to C = C * A
/=	Divide AND assignment operator, It divides left operand with the right operand and assign the result to left operand	C /= A is equivalent to C = C / A
%=	Modulus AND assignment operator, It takes modulus using two operands and assign the result to left operand	C %= A is equivalent to C = C % A
<<=	Left shift AND assignment operator	C <<= 2 is same as C = C << 2
>>=	Right shift AND assignment operator	C >>= 2 is same as C = C >> 2
&=	Bitwise AND assignment operator	C &= 2 is same as C = C & 2
^=	bitwise exclusive OR and assignment operator	C ^= 2 is same as C = C ^ 2
|=	bitwise inclusive OR and assignment operator	C |= 2 is same as C = C | 2

Example:

using System;

namespace OperatorsAppl
{
    class Program
    {
        static void Main(string[] args)
        {
            int a = 23;
            int c;

            c = a;
            Console.WriteLine("Line 1 - =  Value of c = {0}", c);

            c += a;
            Console.WriteLine("Line 2 - += Value of c = {0}", c);

            c -= a;
            Console.WriteLine("Line 3 - -=  Value of c = {0}", c);

            c *= a;
            Console.WriteLine("Line 4 - *=  Value of c = {0}", c);

            c /= a;
            Console.WriteLine("Line 5 - /=  Value of c = {0}", c);

            Console.ReadLine();
        }
    }
}

The above code will result in the following:

Line 1 - =     Value of c = 23
Line 2 - +=    Value of c = 46
Line 3 - -=    Value of c = 23
Line 4 - *=    Value of c = 529
Line 5 - /=    Value of c = 23

Misc Operators

There are few other important operators including sizeof, typeof and ? : supported by C#.

Operator	Description	Example
sizeof()	Returns the size of a data type.	sizeof(int), will return 4.
typeof()	Returns the type of a class.	typeof(StreamReader);
&	Returns the address of an variable.	&a; will give actual address of the variable.
*	Pointer to a variable.	*a; will pointer to a variable.
? :	Conditional Expression	If Condition is true ? Then value X : Otherwise value Y
is	Determines whether an object is of a certain type.	If( Ford is Car) // checks if Ford is an object of the Car class.
as	Cast without raising an exception if the cast fails.	Object obj = new StringReader("Hello"); StringReader r = obj as StringReader;

Example:

using System;

namespace OperatorsAppl
{
    
   class Program
   {
      static void Main(string[] args)
      {
         
         /* example of sizeof operator */
         Console.WriteLine("The size of int is {0}", sizeof(int));
         Console.WriteLine("The size of short is {0}", sizeof(short));
         Console.WriteLine("The size of double is {0}", sizeof(double));
         
         /* example of ternary operator */
         int a, b;
         a = 10;
         b = (a == 1) ? 20 : 30;
         Console.WriteLine("Value of b is {0}", b);

         b = (a == 10) ? 20 : 30;
         Console.WriteLine("Value of b is {0}", b);
         Console.ReadLine();
      }
   }
}

The above code will result in the following:

The size of int is 4
The size of short is 2
The size of double is 8
Value of b is 30
Value of b is 20

Operators Precedence in C#

Operator precedence determines the grouping of terms in an expression. This affects how an expression is evaluated. Certain operators have higher precedence than others; for example, the multiplication operator has higher precedence than the addition operator:

For example x = 7 + 3 * 2; here, x is assigned 13, not 20 because operator * has higher precedence than +, so it first gets multiplied with 3*2 and then adds into 7.

Here, operators with the highest precedence appear at the top of the table, those with the lowest appear at the bottom. Within an expression, higher precedence operators will be evaluated first.

Category	Operator	Associativity
Postfix	() [] -> . ++ - -	Left to right
Unary	+ - ! ~ ++ - - (type)* & sizeof	Right to left
Multiplicative	* / %	Left to right
Additive	+ -	Left to right
Shift	<< >>	Left to right
Relational	< <= > >=	Left to right
Equality	== !=	Left to right
Bitwise AND	&	Left to right
Bitwise XOR	^	Left to right
Bitwise OR	|	Left to right
Logical AND	&&	Left to right
Logical OR	||	Left to right
Conditional	?:	Right to left
Assignment	= += -= *= /= %=>>= <<= &= ^= |=	Right to left
Comma	,	Left to right

Example:

using System;

namespace OperatorsAppl
{
    
   class Program
   {
      static void Main(string[] args)
      {
         int a = 20;
         int b = 10;
         int c = 15;
         int d = 5;
         int e;
         e = (a + b) * c / d;     // ( 30 * 15 ) / 5
         Console.WriteLine("Value of (a + b) * c / d is : {0}", e);

         e = ((a + b) * c) / d;   // (30 * 15 ) / 5
         Console.WriteLine("Value of ((a + b) * c) / d is  : {0}", e);

         e = (a + b) * (c / d);   // (30) * (15/5)
         Console.WriteLine("Value of (a + b) * (c / d) is  : {0}", e);

         e = a + (b * c) / d;    //  20 + (150/5)
         Console.WriteLine("Value of a + (b * c) / d is  : {0}", e);
         Console.ReadLine();
      }
   }
}

The above code will result in the following:

Value of (a + b) * c / d is : 90
Value of ((a + b) * c) / d is  : 90
Value of (a + b) * (c / d) is  : 90
Value of a + (b * c) / d is  : 50