PHP Operators

PHP operators are symbols used to perform operations on variables and values. They are essential for arithmetic calculations, logical comparisons, string manipulations, and more. Understanding PHP operators is crucial for efficient coding and optimizing performance. In this guide, we will explore different types of PHP operators, their functionalities, and practical examples with outputs.

Introduction to PHP Operators

Operators in PHP are categorized based on their functionality. They help in performing mathematical operations, assigning values, comparing data, and controlling program flow. Mastering these operators enhances code efficiency and readability.

1. Arithmetic Operators

Arithmetic operators perform basic mathematical calculations like addition, subtraction, multiplication, and division.

Example:

<?php
$a = 10;
$b = 3;

echo "Addition: " . ($a + $b) . "\n";        // Output: 13
echo "Subtraction: " . ($a - $b) . "\n";     // Output: 7
echo "Multiplication: " . ($a * $b) . "\n";   // Output: 30
echo "Division: " . ($a / $b) . "\n";        // Output: 3.333...
echo "Modulus: " . ($a % $b) . "\n";         // Output: 1
echo "Exponentiation: " . ($a ** $b) . "\n";  // Output: 1000
?>

Output

2. Assignment Operators

Assignment operators assign values to variables. They can also perform operations before assignment.

Examples:

<?php
$x = 5;
$x += 3;  // $x = $x + 3
echo $x;  // Output: 8
?>

Output

3. Comparison Operators

Comparison operators compare two values and return a boolean result (true or false).

Example:

<?php
$a = 5;
$b = "5";

var_dump($a == $b);   // Loose comparison (value only): bool(true)
var_dump($a === $b);  // Strict comparison (value and type): bool(false)
var_dump($a != $b);   // Loose not equal: bool(false)
var_dump($a !== $b);  // Strict not equal: bool(true)
?>

Output

4. Increment/Decrement Operators

These operators increase or decrease a variable's value.

Example:

<?php
$x = 5;
echo "Pre-increment: " . ++$x . "\n";  // Increments then returns: 6
echo "Post-increment: " . $x++ . "\n"; // Returns then increments: 6 (but $x becomes 7)
echo "Final value: " . $x;             // Shows final value: 7
?>

Output

5. Logical Operators

Logical operators combine conditional statements.

Example:

<?php
$a = true;
$b = false;

var_dump($a && $b);  // Logical AND: bool(false)
var_dump($a || $b);  // Logical OR: bool(true)
var_dump(!$a);       // Logical NOT: bool(false)
?>

Output

6. String Operators

PHP has two string operators:

• Concatenation (.)
• Concatenation assignment (.=)

Example

<?php
$str1 = "Hello";
$str2 = "World";

// String concatenation
echo $str1 . " " . $str2 . "\n";  // Output: Hello World

// Compound concatenation
$str1 .= $str2;
echo $str1;  // Output: HelloWorld
?>

Output

7. Array Operators

Array operators compare and combine arrays.

Example:

<?php
$a = ["a" => "apple", "b" => "banana"];
$b = ["b" => "blueberry", "c" => "cherry"];

print_r($a + $b);  // Output: Array ( [a] => apple [b] => banana [c] => cherry )
?>

Output

8. Conditional (Ternary) Operator

The ternary operator (?:) is a shorthand for if-else.

Example

<?php
$age = 20;
echo ($age >= 18) ? "Adult" : "Minor";  // Output: Adult
?>

Output

9. Null Coalescing Operator

The null coalescing operator (??) returns the first non-null value.

Example

<?php
$name = $_GET['name'] ?? 'Guest';
echo $name;  // Output: Guest if 'name' is not set
?>

Output

10. Spaceship Operator (<=>)

The spaceship operator compares two values and returns:

• 0 if equal
• 1 if left is greater
• -1 if right is greater

Example

<?php
echo 5 <=> 3;  // Output: 1
echo 3 <=> 5;  // Output: -1
echo 5 <=> 5;  // Output: 0
?>

Output

11. Bitwise Operators

Bitwise operators perform operations on bits.

Example:

<?php
$a = 5;  // 0101
$b = 3;  // 0011

echo $a & $b;  // Output: 1 (0001)
?>

Output

12. Execution Operator (`)

Executes shell commands.

Example:

<?php
$output = `ls -la`;
echo "<pre>$output</pre>";
?>

13. Type Operator (instanceof)

Checks if an object is an instance of a class.

Example:

<?php
class MyClass {}
$obj = new MyClass();
var_dump($obj instanceof MyClass);  // Output: bool(true)
?>

Output

14. Operator Precedence

Operator precedence determines the order of operations.

Example:

<?php
echo 2 + 3 * 4;  // Output: 14 (Multiplication first)
?>

Output