Get current page url and replace root with a domain

Question

I would like to change the following code in the following way.

The php script gets the current url of the page of mine.

Now since I am using the descriptions of what i have on my another site i would like to put canonical tag on the page.

So I would like the script to get the url of my site and replace the www.mysite.com to www.domain2.com

How do i make it that the ,," will result the url i want? ( so i can make " rel="canonical" />

It can be beneficial for others aswell, who own more sites and have the same description and dont want to get penalized by Google Panda or have product descriptions from manufacturers.

<?php
function curPageURL() {
 $pageURL = 'http';
 if ($_SERVER["HTTPS"] == "on") {$pageURL .= "s";}
 $pageURL .= "://";
 if ($_SERVER["SERVER_PORT"] != "80") {
  $pageURL .= $_SERVER["SERVER_NAME"].":".$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"];
 } else {
  $pageURL .= $_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"];
 }
 return $pageURL;
}
?>

Answer 1

I have finally found a solution to that

<?php
$Get_url = "http://" . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];
echo str_replace("www.mydomain.com", "www.domain2.com", $Get_url);
?>