PHP AND Operator

Summary: in this tutorial, you’ll learn about the PHP AND operator and how to use it to build a complex logical expression.

Introduction to the PHP AND operator #

The logical AND operator accepts two operands and returns true if both operands are true; otherwise, it returns false.

PHP uses the and keyword to represent the logical AND operator:

expression1 and expression2

The following table illustrates the result of the and operator:

Since PHP keywords are case-insensitive, the AND and and operators are the same:

expression1 AND expression2

By convention, you should use the and operator in the lowercase format.

In addition to using the and keyword, PHP uses && as the logical AND operator:

expression1 && expression2

The && and and operators return the same result. The only difference between the && and and operators are their precedences.

The and operator has higher precedence than the && operator. The precedence of an operator specifies the order in which PHP evaluates.

PHP AND operator examples #

Suppose you want to offer discounts to customers who buy more than three items at a price of more than 99. To determine whether customers can get a discount or not, you can use the AND operator as follows:

<?php

$price = 100;
$qty = 5;

$discounted = $qty > 3 && $price > 99;


var_dump($discounted);
Code language: HTML, XML (xml)

Try it

Output:

bool(true)Code language: JavaScript (javascript)

If you change the $qty to 2, the $discounted will be false like this:

<?php

$price = 100;
$qty = 2;

$discounted = $qty > 3 && $price > 99;

var_dump($discounted);Code language: HTML, XML (xml)

Try it

In practice, you’ll use the logical AND operator in the if, if-else, if-elseif, while, and do-while statements.

Short-circuiting #

When the value of the first operand is false, the logical AND operator knows that the result must also be false. In this case, it doesn’t evaluate the second operand. This process is called short-circuiting.

See the following example:

<?php

$debug = false;
$debug && print('PHP and operator demo!');Code language: HTML, XML (xml)

Try it

How it works.

• First, define the variable $debug and initialize it to false.
• Second, use the logical AND operator to combine the $debug and print(). Since $debug is false, PHP doesn’t evaluate the call to the print() function.

If you change the $debug to true, you’ll see a message in the output:

<?php

$debug = true;
$debug && print('PHP and operator demo!');Code language: HTML, XML (xml)

Try it

Output:

PHP and operator demo!Code language: plaintext (plaintext)

Summary #

• Use the PHP AND operator (and, &&) to combine two boolean expressions and return true if both expressions evaluate to true; otherwise, it returns false.
• The logical AND operator is short-circuiting.