PHP redirect not working - php

Question

The code below simple checks if the user enters in a valid JSON data as denoted in the if statement below. The if statement works just fine for me, it's just getting the page to redirect is not. Could anyone explain why this might be? Thanks
<?php
//Retrives name var from form on previous page
$name = $_REQUEST['name'];
//Changes the title tag based on the users name
$pageTitle = "Thanks ".$name."!";
//
$section = "contact";
//Retrives the product ID based on what the user requested
$productId = $_REQUEST['productId'];
//Retrives the email var from form on previous page
$email = $_REQUEST['email'];
?>
<?php
//Acts as a place holder var for the url containing the productID the user specfied.
$url = 'xxx.xxx.xxx';
//Fetchs the contents of the of the url var address, and returns them into a JSON var
$JSON = file_get_contents($url);
//Puts the JSON var into a parameter that actually does the decoding into JSON
$data = json_decode($JSON,true);
if (empty($data)){
header('Location: http://www.google.com');
exit;
} else {
echo "it's valid";
//References the header file for CSS
include("inc/header.php");
}

Answer 1

You send a few whitespaces before the redirect, when you close and reopen php around your line 14.
And Headers cannot be sent after the body of response is already started. (There should be a warning somewhere unless it is turned off.)

Answer 2

There is a whitespace / enter between
?>
<?php
Once you send any char, a redirect is no longer working. Put everything into a single
<?php ... ?>
and it should work.

Answer 3

Just a hunch but try removing the
?>
<?php
in the middle as this might be sending some information to the client before your asking to send the header. This could cause the header redirect to fail.

Answer 4

In your else statement you don't have a header location specified, all you're doing is echoing that it's valid and you're including a file but not redirecting to a different page.
What you have is this:
else {
echo "it's valid";
//References the header file for CSS
include("inc/header.php");
}
Shouldn't you have a header in there?