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PHP Assignment Operators

Assignment operators are used with numeric values to write a value to a variable. The most basic assignment operator is the equal sign (=), which sets the value of the left operand to the value of the expression on the right.

The Basic Assignment (=)

In PHP, the = does not mean "equals" (that is handled by comparison operators). Instead, it means **"set the value of."**

<?php
    $x = 10; // $x now holds the value 10
?>

Table of Assignment Operators

PHP also provides "shorthand" operators that combine a mathematical operation with assignment.

Operator Same as... Description
x = y x = y Assigns value of y to x
x += y x = x + y Addition and assignment
x -= y x = x - y Subtraction and assignment
x *= y x = x * y Multiplication and assignment
x /= y x = x / y Division and assignment
x %= y x = x % y Modulus and assignment

Practical Example

Using shorthand operators makes your code cleaner and easier to read, especially when updating totals in a loop.

<?php
    $total = 100;
    $tax = 15;

    $total += $tax; // Instead of $total = $total + $tax;
    echo $total; // Outputs: 115
?>
Important Distinction: Remember that $x = $y is an **assignment**, while $x == $y is a **comparison**. Distinguishing these two is vital for logic!
String Assignment: You can also use .= to append a string to an existing variable. (e.g., $name .= " Doe";).

Key Points to Remember

  • The = operator sets a value; it doesn't compare them.
  • Shorthand operators (like +=) combine math and assignment.
  • Using shorthand makes code cleaner and more professional.
  • Shorthand math works the same way for subtraction, multiplication, and division.
  • Always remember that the variable being updated must be on the left side.
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