How to use Explode and Implode Functions In PHP

Using Regular Expressions

The basic approach is to split the string into an array of words using the explode() function, reverse the even-length words, and then reconstruct the string using the implode function.

Example: Here, we use explode to split the input string into an array of words, iterate through the words, reverse the even-length ones with strrev() function, and finally join the modified words back into a string using the implode() function.

PHP

<?php 
  
function reverseWords($inputString) { 
    $words = explode(" ", $inputString); 
  
    for ($i = 0; $i < count($words); $i++) { 
        if (strlen($words[$i]) % 2 === 0) { 
            $words[$i] = strrev($words[$i]); 
        } 
    } 
  
    $outputString = implode(" ", $words); 
    return $outputString; 
} 
  
$input = "Welcome to GeeksGeeks"; 
  
$output = reverseWords($input); 
echo $output; 
  
?>

Output

Welcome ot skeeGskeeG

Reversing the Even Length Words of a String in PHP

Reversing the even-length words of a string is a common programming task that involves manipulating individual words within a sentence. In PHP, there are several approaches to achieve this, each offering different levels of complexity and flexibility.

Table of Content