php Replacing multiple spaces with a single space [duplicate]
Use preg_replace() and instead of [ \t\n\r] use \s:
$output = preg_replace('!\s+!', ' ', $input);From Regular Expression Basic Syntax Reference:
\d, \w and \s
Shorthand character classes matching digits, word characters (letters, digits, and underscores), and whitespace (spaces, tabs, and line breaks). Can be used inside and outside character classes.
$output = preg_replace('/\s+/', ' ',$input);\s is shorthand for [ \t\n\r]. Multiple spaces will be replaced with single space.