C# Operator

In C#, operators are special symbols or keywords that are used to perform operations on variables and values. Operators are an essential part of C# programming, enabling developers to manipulate data and variables efficiently.

An operator in C# performs specific mathematical, logical, or bitwise operations, such as addition, subtraction, comparison, and more. They work with operands (variables, values, or expressions) to produce a result.

1. Arithmetic Operators

These operators are used for performing basic mathematical operations.

Operator
Description
Example
+
Addition: Adds two operands.
a+b
Subtraction: Subtracts the second operand from the first.
a-b
*
Multiplication: Multiplies two operands.
a*b
/
Division: Divides the first operand by the second. Returns quotient.
a/b
%
Modulus: Returns the remainder of a division operation.
a%b

Example:


int a = 20;
int b = 5;
Console.WriteLine(a + b);  // Output: 25 (Addition)
Console.WriteLine(a - b);  // Output: 15 (Subtraction)
Console.WriteLine(a * b);  // Output: 100 (Multiplication)
Console.WriteLine(a / b);  // Output: 4  (Division)
Console.WriteLine(a % b);  // Output: 0  (Remainder)

Note:

  1. When dividing two integers (int type), C# performs integer division and discards any fractional part.
  2. To get a floating-point result, one of the operands must be a floating-point type (e.g., double or float).

2. Relational (Comparison) Operators

These operators are used to compare two values. They return a boolean value (true or false).

Operator
Description
Example
==
Equal to: Returns true if both operands are equal.
a == b
!=
Not equal to: Returns true if operands are not equal.
a != b
>
Greater than: Returns true if the left operand is greater.
a > b
<
Less than: Returns true if the left operand is smaller.
a < b
>=
Greater than or equal to: Returns true if left operand is greater or equal.
a >= b
<=
Less than or equal to: Returns true if left operand is smaller or equal.
a <= b


Example:


int a = 20;
int b = 5;
Console.WriteLine(a == b);  // Output: false
Console.WriteLine(a != b);  // Output: true
Console.WriteLine(a > b);  // Output: true
Console.WriteLine(a < b);  // Output: false
Console.WriteLine(a >= b);  // Output: true
Console.WriteLine(a <= b);  // Output: false

3. Logical Operators

Logical operators are used to combine conditional statements.

Operator
Description
Example
&&
Logical AND: Returns true if both operands are true.
a && b
||
Logical OR: Returns true if at least one operands is true.
a || b
!
Logical NOT: Reverses the logical state of its operand.
!a


Example:


bool a = true;
bool b = false;

Console.WriteLine(a && b);  // Output: False (Both must be true)
Console.WriteLine(a || b);  // Output: True (At least one is true)
Console.WriteLine(!a);      // Output: False (Reverses the value)

4. Assignment Operators

These are used to assign values to variables. Some assignment operators combine arithmetic operations with assignment.

Operator
Description
Example
=
Assignment: Assigns the value on the right to the variable on the left.
a = b
+=
Add and assign: Adds the right operand to the left operand and assigns the result to the left operand.
a += b
-=
Subtract and assign: Subtracts the right operand from the left operand and assigns the result to the left operand.
a -= b
*=
Multiply and assign: Multiplies the left operand by the right operand and assigns the result to the left operand.
a *= b
/=
Divide and assign: Divides the left operand by the right operand and assigns the result to the left operand.
a /= b
%=
Modulus and assign: Takes the modulus of the left operand by the right operand and assigns the result to the left operand.
a %= b


Example:


int a = 20;
a += 10;  // a = a + 10 => num = 30
a -= 5;  // a = a - 5 => a = 25
a *= 2;  // a = a * 2 => a = 50
a /= 5;  // a = a / 5 => a = 10

Console.WriteLine(a);  // Output: 10

5. Ternary Operator

This is a shorthand for an if-else statement.

Syntax:


condition ? expression_if_true : expression_if_false

Example:


int age = 19;
string result = (age >= 18) ? 'Adult': 'Not Adult';
Console.WriteLine(result);  // Output: Adult

6. Unary Operators

These operators operate on a single operand.

Operator
Description
Example
++
Increment: Increases the operand by 1. Can be used in pre or post increment form.
++a or a++
--
Decrement: Decreases the operand by 1. Can be used in pre or post decrement form.
--a or a--
+
Unary plus: Indicates a positive value.
+a
-
Unary minus: Negates the operand.
-a
!
Logical NOT: Reverses the logical state of its operand.
!a


Example:


int x = 20;
Console.WriteLine(++x);  // Output: 21 (Pre-increment)
Console.WriteLine(x++);  // Output: 21 (Post-increment)
Console.WriteLine(x);    // Output: 22 (x is now 22)