Reverse words in a given string in PHP

In this tutorial, we will learn how to reverse strings and eventually words in a given string in PHP.

It has many built-in methods which can be used for building more dynamic and interactive web pages.

We can reverse a word in a string in PHP in many ways. We will see some of them here.

Basic Usage

Before we see how to reverse words in a string, we will see how to reverse a string in PHP.

Method 1 – Using a for loop

Given below is an illustration for reversing a string using a simple for loop.

<?php
   #reverseString method
   function reverseString($inpStr)
   {
      echo "The reversed string is: ";
      for ($i = strlen($inpStr)-1; $i >= 0; $i--)
      {
         echo $inpStr[$i];
      }
   echo $revStr;
   }

   #driver
   $inpStr = "CodeSpeedy Technologies";
   reverseString($inpStr);
?>

Output

The reversed string is: seigolonhceT ydeepSedoC

Explanation
We use the for loop to index through each character in the string and print it.

Method 2 – Using the built-in method strrev()

Given below is the illustration for reversing a string using strrev() method.

<?php
   #reverseString method
   function reverseString($inpStr)
   {
      return strrev($inpStr);
   }

   #driver
   $inpStr = "CodeSpeedy Technologies";
   echo "The reversed string is: " . reverseString($inpStr);
?>

Output

The reversed string is: seigolonhceT ydeepSedoC

Explanation
We use the built-in method ‘strrev()’ for reversing the string. We create a function named ‘reverseString()’ with the input string as its parameter and return the reverse of the string from it.

Now, we will see how to reverse words in a string. Given below is the illustration for the following to reverse the words in a string.

<?php
   $inpStr = "CodeSpeedy Technologies";
   $inpStrArray = explode(" ", $inpStr); #converting string to array
   $revArr = array_reverse($inpStrArray); #reversing the array
   echo "The reversed string words are: " . $revStr = implode(" ", $revArr); #joining the array back to string
?>

Output

The reversed string words are: Technologies CodeSpeedy

Explanation
In the following program, we convert the string to an array by splitting it with spaces. We are reversing the array using the ‘array_reverse()’ method and again joining the array back to form a string to print the reversed words string.