php - How to pass the require_once output to a variable?

Question

I want to call require_once("test.php") but not display result and save it into variable like this:

$test = require_once('test.php');

//some operations like $test = preg_replace(…);

echo $test;

Solution:

test.php

<?php
$var = '/img/hello.jpg';

$res = <<<test

<style type="text/css">
body{background:url($var)#fff !important;}
</style>

test;

return $res;
?>

main.php

<?php
$test = require_once('test.php');

echo $test;
?>

Answer 1

Is it possible?

Yes, but you need to do an explicit return in the required file:

//test.php

<? $result = "Hello, world!"; 
  return $result;
?>

//index.php

$test = require_once('test.php');  // Will contain "Hello, world!"

This is rarely useful - check Konrad's output buffer based answer, or adam's file_get_contents one - they are probably better suited to what you want.