How to check for an empty array using PHP

To check whether an array is empty or not in PHP, you can use the logical not operator using the bang symbol (!).

Here’s an example of checking whether the $list array is empty:

<?php

$list = [];

if (!$list) {
  print "list is empty";
} else {
  print "list has values!";
}

// Output: list is empty

To check whether the $list array is empty or not, you create an if condition that checks whether the $list value is falsy (!$list).

But if you haven’t declared the variable, the not operator will trigger a PHP warning:

<?php
// no declaration of $list in this code

// 👇 Warning: Undefined variable $list
if (!$list) {
  print "list is empty";
} else {
  print "list has values!";
}

To avoid PHP undefined variable warning, you can use the empty() function in place of the not operator.

The empty() function checks for two conditions:

1. Whether a variable exists or not
2. Whether the variable has value or not

The function returns false when the variable exists and is not empty. Otherwise, it returns true.

Here’s an example of using empty() to check for an empty array:

<?php

if (empty($list)) {
  print "list is empty";
} else {
  print "list has values!";
}

// Output: list is empty

By calling the empty() function, you avoid the PHP warning when the variable has not been declared.

Now you’ve learned how to check for empty arrays in PHP. Nice!