How to check if a String Contains a Substring in PHP ?

Checking whether a string contains a specific substring is a common task in PHP. Whether you're parsing user input, filtering content, or building search functionality, substring checking plays a crucial role.

Methods

Below are the following methods by which we can check if a string contains a substring in PHP:

1. Using str_contains() (PHP 8+)

<?php
  $text = "Welcome to Empowerfit!";
if (str_contains($text, "Empower")) {
    echo "Substring found!";
} else {
    echo "Substring not found.";
}
?>

Output:

Substring found!

2. Using strpos() (All PHP versions)

<?php
    $text = "Learn PHP programming";
if (strpos($text, "PHP") !== false) {
    echo "Substring found!";
} else {
    echo "Substring not found.";
}

?>

Output:

Substring found!

3. Case-Insensitive Search with stripos()

<?php
  $text = "Power of Coding";
if (stripos($text, "power") !== false) {
    echo "Substring found (case-insensitive)!";
}

?>

Output:

Substring found (case-insensitive)!

4. Using Regular Expressions with preg_match()

<?php
 $text = "Develop with PHP";
if (preg_match("/PHP/", $text)) {
    echo "Match found using regex.";
}

?>

Best Practices

• Use str_contains() for simple checks (if PHP 8+).
• Always check strpos with !== false, not != false.
• Use stripos() for case-insensitive searches.
• Prefer preg_match() only for complex pattern matching.