How to Search for a String with the PHP strstr() Function

09/04/2021

Contents

In this article, you will learn how to search for a string with the PHP strstr() function.

PHP strstr() Function

The strstr() function in PHP is used to search for the first occurrence of a string within another string. The function takes two parameters: $string (the string to search in) and $search (the string to search for).

Here’s an example of how to use the strstr() function:

<?php
  $string = "How to search for a string with the php strstr() function";
  $search = "search";
  $result = strstr($string, $search);
  echo $result;
?>

This will output:

search for a string with the php strstr() function

The strstr() function returns the portion of $string starting from the first occurrence of $search to the end of $string.

It also has an optional third parameter which is a boolean value, if passed true it returns the part of $string before $search and if passed false it returns the part of $string after $search.

<?php
  $string = "How to search for a string with the php strstr() function";
  $search = "search";
  $result = strstr($string, $search, true);
  echo $result;
?>

This will output:

How to
 

If $search is not found in $string, the function will return false. You can use the === operator to check if $search was found in $string:

<?php
  if ($result === false) {
    echo "$search was not found in $string.";
  } else {
    echo "$search was found in $string.";
  }
?>
 

If $search is an empty string, strstr() will return an empty string. If $search is at the beginning of $string, strstr() will return $string.

You can also use strstr() with arrays, in this case it will search for the first matching value in the array.

Note that the strstr() function is case-sensitive, so if you want to perform a case-insensitive search, you can use the stristr() function instead.

#PHP