remove all spaces php

$string = preg_replace('/\s+/', '', $string);

phpCopy<?php 
$searchString = " ";
$replaceString = "";
$originalString = "This is a programming tutorial"; 
 
$outputString = preg_replace('/\s+/', '', $originalString); 
echo("The original string is: $originalString \n");  
echo("The string without spaces is: $outputString \n"); 
?> 

phpCopy<?php 
$searchString = " ";
$replaceString = "";
$originalString = "This is a programming tutorial"; 
 
$outputString = str_replace($searchString, $replaceString, $originalString); 
echo("The original string is: $originalString \n");  
echo("The string without spaces is: $outputString"); 
  
?>