Remove question mark added to url using form 'get' method - php

Question

I am using a form and the 'get' method to offer users a return option to an unknown url that they came from within my site, as per the code below. I prefer this to just the browsers back button and it works without javascript.
The problem I am having is that some browsers (chrome, safari, there may be others) are adding a question mark to the end of the url they are referred back to. I don't want this for seo reasons.
My question is either:
1) Can I prevent the question mark within my php code somehow; or
2) Please could somebody show me how to redirect the url using htaccess, I potentially have urls that could end:-
.html?
.htm?
.php?
/?
Thanks in advance.
<?php
if (isset ($_SERVER['HTTP_REFERER']) ) {
$url = htmlspecialchars($_SERVER['HTTP_REFERER']);
echo '<br /><form action="' . $url . '" method="get">
<div id="submit"><input type="submit" value="Return to previous page" /></div>
</form>';
}
?>

Answer 1

The ? probably gets added because you're doing a GET request from a form.
Why not do something like:
<input type="button" onclick='document.location.href=<?php echo json_encode($url);?>'>;

Answer 2

use POST method instead of GET

Answer 3

Is it pertinent that you use a form for this? Why not use a hyperlink and style it to look however you want with CSS?
You could use try using a button instead of creating an input value that will be passed.
<form action="url" method="get">
<button type="submit">Return to previous page</button>
</form>

Answer 4

Instead of posting to random URLs (which is not really a good idea) consider using redirects
A solution would be
<?php
if (isset ($_SERVER['HTTP_REFERER']) ) {
$url = htmlspecialchars($_SERVER['HTTP_REFERER'],ENT_QUOTES,'UTF-8');
echo '<br /><form action="redirect.php" method="get">
<input type="hidden" name="return" value="'.$url.'">
<div id="submit"><input type="submit" value="Return to previous page" /></div>
</form>';
}
?>
then in redirect.php
<?php
if (isset ($_GET['return'] ) {
$url = $_GET['return'];
header('Location: '.$url, true, 303); // or 302 for compatibility reasons
echo 'Continue';
exit;
}else{
echo 'Error, no redirect specified';
}
you can replace action="GET" and $_GET with action="POST" and $_POST and it will work the same.
or simply
if (isset ($_SERVER['HTTP_REFERER']) ) {
$url = htmlspecialchars($_SERVER['HTTP_REFERER'],ENT_QUOTES,'UTF-8');
echo 'Return to previous page';
}
both will still create a new history entry in the browser.

Answer 5

In the htaccess you should have something like this:
RewriteEngine on
RewriteRule ^myPage-([a-zA-Z0-9_]*).html myPHPfile.php?var=$1
By the above piece added to your htaccess, when a URL like myPage-whatever.html is called, it's just like calling myPHPfile.php?var=whatever