Obafemi Emmanuel

In PHP, assignment operators are used to assign values to variables. These operators not only assign values but also perform operations simultaneously. Understanding how they work is crucial for writing efficient and concise code.

In this blog, we will explore different types of assignment operators in PHP, their usage, and practical examples to illustrate their functionality.

1. Basic Assignment Operator (=)

The simplest and most commonly used assignment operator is the equal sign (=). It assigns the value on the right to the variable on the left.

Example:

$x = 10; // Assigns 10 to $x
echo $x; // Output: 10

2. Combined Assignment Operators

PHP provides several shorthand assignment operators that perform an operation and assign the result in a single step. These operators save time and make the code more readable.

2.1 Addition Assignment (+=)

This operator adds the right-hand value to the left-hand variable and assigns the result to the variable.

Example:

$x = 5;
$x += 3; // Equivalent to $x = $x + 3;
echo $x; // Output: 8

2.2 Subtraction Assignment (-=)

This operator subtracts the right-hand value from the left-hand variable and assigns the result.

Example:

$x = 10;
$x -= 4; // Equivalent to $x = $x - 4;
echo $x; // Output: 6

2.3 Multiplication Assignment (*=)

This operator multiplies the left-hand variable by the right-hand value and assigns the result.

Example:

$x = 7;
$x *= 2; // Equivalent to $x = $x * 2;
echo $x; // Output: 14

2.4 Division Assignment (/=)

This operator divides the left-hand variable by the right-hand value and assigns the quotient.

Example:

$x = 20;
$x /= 5; // Equivalent to $x = $x / 5;
echo $x; // Output: 4

2.5 Modulus Assignment (%=)

This operator finds the remainder when the left-hand variable is divided by the right-hand value and assigns the result.

Example:

$x = 17;
$x %= 3; // Equivalent to $x = $x % 3;
echo $x; // Output: 2

2.6 Exponentiation Assignment (**=)

This operator raises the left-hand variable to the power of the right-hand value and assigns the result.

Example:

$x = 3;
$x **= 3; // Equivalent to $x = $x ** 3;
echo $x; // Output: 27

3. Bitwise Assignment Operators

Bitwise assignment operators perform bitwise operations and assign the result.

3.1 Bitwise AND Assignment (&=)

This operator performs a bitwise AND operation and assigns the result.

Example:

$x = 5; // 101 in binary
$x &= 3; // 011 in binary
// 101 & 011 = 001 (1 in decimal)
echo $x; // Output: 1

3.2 Bitwise OR Assignment (|=)

This operator performs a bitwise OR operation and assigns the result.

Example:

$x = 5; // 101 in binary
$x |= 3; // 011 in binary
// 101 | 011 = 111 (7 in decimal)
echo $x; // Output: 7

3.3 Bitwise XOR Assignment (^=)

This operator performs a bitwise XOR operation and assigns the result.

Example:

$x = 5; // 101 in binary
$x ^= 3; // 011 in binary
// 101 ^ 011 = 110 (6 in decimal)
echo $x; // Output: 6

3.4 Left Shift Assignment (<<=)

This operator shifts bits to the left and assigns the result.

Example:

$x = 5; // 101 in binary
$x <<= 2; // Shift left by 2 bits
// 10100 in binary (20 in decimal)
echo $x; // Output: 20

3.5 Right Shift Assignment (>>=)

This operator shifts bits to the right and assigns the result.

Example:

$x = 20; // 10100 in binary
$x >>= 2; // Shift right by 2 bits
// 101 in binary (5 in decimal)
echo $x; // Output: 5

Conclusion

PHP assignment operators simplify operations by combining them with variable assignments. Understanding these operators helps write cleaner and more efficient code. From basic assignment (=) to arithmetic (+=, -=, etc.) and bitwise (&=, |=, etc.) operators, each plays a significant role in PHP development.

By mastering assignment operators, you can enhance your PHP programming skills and write more optimized scripts.