C# Operators Tutorial

In this tutorial lesson we learn the different operators, with explanations and examples, available in C#. This tutorial covers arithmetic, comparison, logical, assignment and bitwise operators.

Here's a table of contents of what you'll learn in this lesson:
(click on a link to skip to its section)

Let's jump right in.

What are operators

An operator is a symbol that has a special meaning in C#. They indicate the types of operations that can be done within our code, such as mathematical or logical manipulations.

C# provides us with the following operators:

  • Arithmetic Operators
  • Comparison Operators
  • Logical Operators
  • Assignment Operators
  • Bitwise Operators
  • Other Operators

Throughout the tutorial series we’ll be using many of these and their uses will become clearer.

Arithmetic operators

We use arithmetic operators in computations where we’re working with numbers.

The following table shows all the arithmetic operators supported by C#:

NameOperatorExampleSame as
Add+a + b 
Subtract-a - b 
Multiply*a * b 
Divide/a / b 
Modulus%a % b 
Increment++a++a + 1
Decrement--b--b - 1
Example:
using System;

namespace Operators
{
    class Program
    {
        static void Main(string[] args)
        {
            // Add
            Console.WriteLine("10 + 5 = {0}", 10 + 5);

            // Subtract
            Console.WriteLine("15 - 3 = {0}", 15 - 3);

            // Multiply
            Console.WriteLine("2 * 2 = {0}", 2 * 2);

            // Divide
            Console.WriteLine("27 / 25 = {0}", 27 / 25);

            // Modulus (remainder of division)
            // 27 divided by 25 is 1, with 2 remaining
            Console.WriteLine("27 % 25 = {0}", 27 % 25);

            // Increment
            int a = 1;
            a++;
            Console.WriteLine("1++ = {0}", a);

            // Decrement
            a = 5;
            a--;
            Console.WriteLine("5-- = {0}", a);


            Console.ReadLine();
        }
    }
}

Comparison operators

We use comparison operators in to compare values.

The following table shows all the comparison operators supported by C#:

NameOperatorExampleResult
Equal==1 == 1true
Not Equal!=1 != 1false
Greater than>2 > 1true
Greater than or equal to>=1 >= 1true
Less than<2 < 1false
Less than or equal to<=1 <= 2true
Example:
using System;

namespace Operators
{
    class Program
    {
        static void Main(string[] args)
        {
            // Equal
            Console.WriteLine("1 == 1: {0}", 1 == 1);

            // Not equal
            Console.WriteLine("1 != 1: {0}", 1 != 1);

            // Greater than
            Console.WriteLine("1 > 2: {0}", 1 > 2);

            // Greater than or equal to
            Console.WriteLine("1 >= 1: {0}", 1 >= 1);

            // Less than
            Console.WriteLine("2 < 1: {0}", 2 < 1);

            // Less than or equal to
            Console.WriteLine("1 <= 1: {0}", 1 <= 1);


            Console.ReadLine();
        }
    }
}

Logical operators

Logical operations are part of boolean algebra, which is often taught to computer science students.

In boolean algebra, the value can only be true or false, also denoted 1 and 0 respectively.

The main operations of boolean algebra are conjunction (AND), disjunction (OR), and negation (NOT).

OperatorDescriptionExample
&&AND2 > 1 && 2 < 3
||OR2 != 1 || 1 == 1
!NOT!true
Example:
using System;

namespace Operators
{
    class Program
    {
        static void Main(string[] args)
        {
            // AND
            // one thing AND another
            Console.WriteLine("AND: {0}", 2 > 1 && 2 < 3);

            // OR
            // one thing OR another
            Console.WriteLine("OR: {0}", 2 != 1 || 3 == 1);

            // NOT
            // not a thing
            Console.WriteLine("NOT: {0}", !true);


            Console.ReadLine();
        }
    }
}

Assignment operators

Assignment operators are used to assign values

The following table shows all the assignment operators supported by C#:

NameOperatorExampleSame as
Assign=a = 2 
Add & Assign+=a += 2a = a + 2
Subtract & Assign-=a -= 2a = a - 2
Multiply & Assign*=a *= 2a = a* 2
Divide & Assign/=a /= 2a = a / 2
Modulus & Assign%=a %= 2a = a % 2

The following table shows all the bitwise assignment operators supported by C#:

NameOperatorExampleSame as
Left shift & Assign<<=a <<= 2a = a << 2
Right shift & Assign>>=a >>= 2a = a >> 2
Bitwise AND & Assign&=a &= 2a = a & 2
Bitwise XOR & Assign^=a ^= 2a = a ^ 2
Bitwise OR & Assign|=a |= 2a = a |= 2
Example:
using System;

namespace Operators
{
    class Program
    {
        static void Main(string[] args)
        {
            // Value assignment
            int a = 1;
            Console.WriteLine("=  {0}", a);

            // Add & assign
            a += 2;
            Console.WriteLine("+= 2:  {0}", a);

            // Subtract & assign
            a -= 1;
            Console.WriteLine("-= 1:  {0}", a);

            // Multiply & assign
            a *= 5;
            Console.WriteLine("*= 5:  {0}", a);

            // Divide & assign
            a /= 2;
            Console.WriteLine("/= 2:  {0}", a);

            // Modulus & assign
            a %= 2;
            Console.WriteLine("%= 2:  {0}", a);

            // Bitwise left shift and assign
            a <<= 2;
            Console.WriteLine("<<= 2:  {0}", a);

            // Bitwise right shift and assign
            a >>= 2;
            Console.WriteLine(">>= 2:  {0}", a);

            // Bitwise AND & assign
            a &= 2;
            Console.WriteLine("&= 2:  {0}", a);

            // Bitwise XOR (exclusive or) & assign
            a ^= 2;
            Console.WriteLine("^= 2:  {0}", a);

            // Bitwise OR (inclusive or) & assign
            a |= 2;
            Console.WriteLine("|= 2:  {0}", a);


            Console.ReadLine();
        }
    }
}

Bitwise operators

Bitwise operators are often used in low-level programming, like working with the Windows API, or encryption, or websockets.

The following table shows all the bitwise operators supported by C#:

OperatorDescription
&Binary AND
|Binary OR
^Binary XOR
~Binary Complement
<<Binary Left Shift
>>Binary Right Shift

Other operators

There are a few other operators in C# that we need to be aware of. We’ll go through them as needed throughout the tutorial series.

OperatorDescription
sizeof()Returns the bit size of a data type
typeof()Returns the type of a class
&Returns the address in memory of a variable
*Pointer to a variable
? :Shortened conditional expression (ternary)
isDetermines whether a class object is of a certain type
asDo a cast without throwing an exception (error) if the cast fails

Summary: Points to remember

  • Operators are symbols in C# that have special meaning and allow us to perform operations and manipulations on our code.