php include或include_once函数不起作用

Question

I have php code in parameter_file.php file as below. when i called this file in index.php file, its not reading any values ! Both the files are present under same directory and using latest php 5.4

parameter_file.php

<?php
$color='red';
$car='BMW';
?>

Body of index.php

<?php include 'parameter_file.php';
echo  "value is : ".$color;
?>

Could you please tell where/what the problem is ?

Answer 1

error_reporting(E_ALL) helped to find where the issue is... the problem was both the files are present in same folder but under different sub domain. I have corrected it ., worked fine.