As a PHP developer, you’ll often find yourself performing calculations and operations on variables, and assigning the results to other variables. This is where assignment operators come in. PHP assignment operators allow you to perform an operation and assign the result to a variable in a single statement.In this article, we’ll take a comprehensive look at the different types of PHP assignment operators and how to use them.

Table Of Contents

Firstly, The most common assignment operator in PHP is the equals sign (=). For example, the following code assigns the value 10 to the variable $x:

<?php 
$x = 10;

Let’s see each one with examples:

PHP Arithmetic Assignment Operators

Arithmetic operators are used to perform mathematical operations on numeric data. PHP arithmetic assignment operators perform arithmetic operations. The arithmetic assignment operators are:

  • += or $x + $y (Addition Assignment Operator)
  • -= or $x - $y (Subtraction Assignment Operator)
  • *= or $x * $y (Multiplication Assignment Operator)
  • /= or $x / $y (Division Assignment Operator)
  • %= or $x % $y (Modulus Assignment Operator)
  • **= or $x ** $y (Exponentiation Assignment Operator)

Let’s take a look at an example:

<?php 
$x = 10;
$x += 5; // equivalent to $x = $x + 5
echo $x; // Output: 15

In this example, we’re adding 5 to the value of $x using the addition assignment operator. The result is then assigned to $x, and the output is 15.

So, you can use the arithmetic assignment operators to perform complex calculations in a single statement, which makes your code more concise and easier to read. To learn more details about it, read this tutorial.

PHP Bitwise Assignment Operators

Furthermore, developers use bitwise operators to manipulate data at the bit level. PHP bitwise assignment operators perform bitwise operations. The bitwise assignment operators are:

  • &= or $x & $y (Bitwise AND Assignment Operator)
  • |= or $x | $y (Bitwise OR Assignment Operator)
  • ^= or $x ^ $y (Bitwise XOR Assignment Operator)
  • <<= or $x << $y (Left Shift Assignment Operator)
  • >>= or $x >> $y (Right Shift Assignment Operator)

Let’s take a look at an example:

<?php 
$x = 5;
$x |= 2; // equivalent to $x = $x | 2
echo $x; // Output: 7

In this example, we’re performing a bitwise OR operation between the values of $x and 2 using the bitwise OR assignment operator. The result is then assigned to $x, and the output is 7.

So, you can use the bitwise assignment operators to perform complex bitwise operations in a single statement, which makes your code more concise and easier to read. To learn more details about it, read this tutorial.

Null Coalescing Operator

Furthermore, developers use the null coalescing operator to assign a default value to a variable if it is null. The null coalescing operator is:

  • ?? (Null Coalescing Operator)

Let’s take a look at an example:

<?php 
$name = null;
$fullName = $name ?? 'John Doe';
echo $fullName; // Output: John Doe

In this example, we’re assigning the value ‘John Doe’ to the variable $fullName using the null coalescing operator. If $name is null, the value ‘John Doe’ will be assigned to $fullName.

So, the null coalescing operator can be used to assign default values to variables, which can simplify your code and make it more readable. To learn more details about it, read this tutorial.

Assign a Reference to a PHP Variable

Furthermore, people use the reference assignment operator to assign a reference to a variable, rather than copying the value of the variable. The reference assignment operator is:

  • =& (Reference Assignment Operator)

Let’s take a look at an example:

<?php 
$x = 5;
$y =& $x;
$x = 10;
echo $y; // Output: 10

In this example, we’re creating a reference to the variable $x using the reference assignment operator. We then assign the value 10 to $x, and output the value of $y. Since $y is a reference to $x, it also changes to 10, and the output is 10.

The reference assignment operator can be useful when working with large data sets, as it allows you to avoid copying large amounts of data.

Other Assignment Operators

In addition to the arithmetic, bitwise, null coalescing, and reference assignment operators, PHP also provides other assignment operators for specific use cases. These operators are:

  • .= (Concatenation Assignment Operator)
  • ??= (Null Coalescing Assignment Operator)

So, Let’s take a look at each of these operators in turn:

Concatenation Assignment Operator: used to concatenate a string onto the end of another string. For an example:

<?php 
$string1 = 'Hello';
$string2 = ' World!';
$string1 .= $string2; // equivalent to $string1 = $string1 . $string2
echo $string1; // Output: Hello World!

In this example, we’re concatenating the value of $string2 onto the end of $string1 using the concatenation assignment operator. The result is then assigned to $string1, and the output is “Hello World!”.

In another hand, the Null Coalescing Assignment Operator: used to assign a default value to a variable if it is null. For example:

<?php 
$name = null;
$name ??= 'John Doe';
echo $name; // Output: John Doe

In this example, we’re assigning the value ‘John Doe’ to the variable $name using the null coalescing assignment operator. If $name is null, the value ‘John Doe’ will be assigned to $name.

Wrapping Up

In conclusion, we’ve taken a comprehensive look at the different types of PHP assignment operators and how to use them.

So, the Assignment operators are an essential tool for any PHP developer, allowing you to perform calculations and operations on variables and assign the results to other variables in a single statement.

Furthermore, you can make your code more concise and easier to read, and avoid common programming errors using assignment operators.

To learn more, visit PHP Manual.