The php_strip_whitespace() is an inbuilt function in PHP which is used to remove all comments and whitespace from the source code.
Syntax:
string php_strip_whitespace ( $file )
Parameters: The php_strip_whitespace() function accepts a single parameter $file. It is a mandatory parameter which specifies the file.
Return value: It returns the source code of $file after removing the comments and whitespace on success otherwise it returns an empty string.
Exceptions:
- It works on PHP 5.0.1 and later versions, it returns an empty string in previous versions.
- This function works similar as php -w command line.
Below programs illustrate the php_strip_whitespace() function in PHP:
Program:
| <?php // Simple program to remove comment // using php_strip_whitespace function.   Â// function to calculate fibonacci number functionfib($n) {     if($n<= 1)         return$n;     returnfib($n- 1) + fib($n- 2); }   Â// Driver Code $n= 9; fib($n);  Â/* * One more multiline comment  */ Âechophp_strip_whitespace(__FILE__);  Â// This line also removed  ?>  | 
<?php
function fib($n) { if ($n <= 1) return $n; 
return fib($n - 1) + fib($n - 2); } $n = 9;
fib($n); echo php_strip_whitespace(__FILE__); 
?>
Reference: http://php.net/manual/en/function.php-strip-whitespace.php

 
                                    







