How Can You Find Strings Within Strings in PHP?

Finding Words Within Strings: Unveiling the Secrets of PHP

In the realm of programming, identifying whether a specific word exists within a larger string can be a common task. PHP, a widely-used scripting language, offers a versatile arsenal of functions to cater to this need.

strpos() and Its Case-Insensitive Counterpart: stripos()

The strpos() function stands as a straightforward and efficient choice for locating the position of a substring within a string. Its case-sensitive nature, however, may limit its usefulness in certain scenarios. To accommodate case-insensitive searches, PHP provides the stripos() function as a viable alternative.

<code class="php">$needle = "to";
$haystack = "I go to school";

if (strpos($haystack, $needle) !== false) echo "Found!";</code>

strstr() and stristr(): Search and Retrieve

The strstr() and stristr() functions combine substring detection with the ability to retrieve the portion of the string following the match. They operate similarly to strpos() and stripos() in terms of case sensitivity.

<code class="php">if (strstr($haystack, $needle)) echo "Found!";</code>

preg_match(): Unleashing Regular Expressions

For scenarios requiring advanced pattern matching, preg_match() emerges as a powerful tool. Regular expressions, supported by preg_match(), allow flexible and intricate searches that go beyond simple string comparisons.

<code class="php">if (preg_match("/to/", $haystack)) echo "Found!";</code>

match_my_string(): Encapsulating the Functionality

To streamline the implementation of word search functionality, a custom function can be created:

<code class="php">function match_my_string($needle = 'to', $haystack = 'I go to school') {
  if (strpos($haystack, $needle) !== false) return true;
  else return false;
}</code>

str_contains(): A PHP 8.0 Delight

PHP 8.0.0 introduced str_contains, a dedicated function for checking if a string contains another. It offers a concise and intuitive syntax:

<code class="php">if (str_contains($haystack, $needle)) {
    echo "Found";
}</code>

The above is the detailed content of How Can You Find Strings Within Strings in PHP?. For more information, please follow other related articles on the PHP Chinese website!