PHP

php replace spaces with dash

str_replace(' ', '-', $string);

php replace space with dash

<?php 
  $string = "hello php";
  $replace = str_replace(" ", "_", $string);
  echo $replace; // hello_php
?>

php replace all spaces with dashes

// Clean up multiple dashes or whitespaces
$string = preg_replace("/[s-]+/", " ", $string);
// Convert whitespaces and underscore to dash
$string = preg_replace("/[s_]/", "-", $string);