Hello there, i have one problem and i dont know how to fix ...

my command:

<?php
 if (preg_match("~^http://www.google.com~i", $_SERVER['HTTP_REFERER']))
  {
  echo 'Google Referer';
  } else {
  echo 'No Referer';
  } 
 }
?>

how i can add 2 preg_match ? example: if http://www.google.com and http://search.yahoo.com = $_SERVER['HTTP_REFERER'] echo 'Google Referer';

and one more thing, how i can add just google.com no "~^http://www.google.com~i" i try "~^google.com~i" but its not working ...

PHP Code:

<?php
 if (preg_match('(.*google.com.*)', $_SERVER['HTTP_REFERER']) || preg_match('(.*search.yahoo.com.*)', $_SERVER['HTTP_REFERER']))
  {
  echo 'Google Referer';
  } else {
  echo 'No Referer';
  } 
 }
?>

You could try something like that.

No need to use a regular expression. One of my favorite PHP functions is this: strpos(). It returns the position that a string was found, and is also very handy for finding out if it exists within any string. For simple matches this is all that is needed.

hello there, thanks for all your answer help me alot !

i have one more question if someone can help me

------------------------------------
website url: http://www.website.com/?w=youtube.com

$w = $_REQUEST['w'];
if ($w != "youtube.com") { } else { echo 'youtube.com'; }
------------------------------------

------------------------------------
website url: http://www.website.com/?w=google.com

$w = $_REQUEST['w'];
if ($w != "google.com") { } else { echo 'google.com'; }
------------------------------------

how i can make if $w is not youtube.com or google.com (or is another link example: facebook.com) to show echo 'none';

If you do decide to use strpos instead of regular expressions here's how:

PHP Code:

<?php

if (strpos($_SERVER['HTTP_REFERER'], "google")) {
    echo "Google Referer";
} else {
    echo "No Referer";
}

?>

Originally Posted by ZoC

hello there, thanks for all your answer help me alot !

i have one more question if someone can help me

------------------------------------
website url: http://www.website.com/?w=youtube.com

$w = $_REQUEST['w'];
if ($w != "youtube.com") { } else { echo 'youtube.com'; }
------------------------------------

------------------------------------
website url: http://www.website.com/?w=google.com

$w = $_REQUEST['w'];
if ($w != "google.com") { } else { echo 'google.com'; }
------------------------------------

how i can make if $w is not youtube.com or google.com (or is another link example: facebook.com) to show echo 'none';

I'm not sure I understand your question properly, but maybye this is what you mean:

PHP Code:

website url: http://www.website.com/?w=youtube.com

$w = $_REQUEST['w'];
if ($w != "youtube.com") { echo 'None' } else { echo 'youtube.com'; }

website url: http://www.website.com/?w=google.com

$w = $_REQUEST['w'];
if ($w != "google.com") { echo 'None' } else { echo 'google.com'; } 


Originally Posted by Marik

If you do decide to use strpos instead of regular expressions here's how:

PHP Code:

<?php

if (strpos($_SERVER['HTTP_REFERER'], "google")) {
    echo "Google Referer";
} else {
    echo "No Referer";
}

?>

Actually, that's not quite how I'd do it. Although it will work, it would also match websites such as ihategoogle.com, or googlerules.com or googlesucks.com or anything that has the "google" substring in it, even just a link from a site with a directory called or containing google.

but:

PHP Code:

if (strpos($_SERVER['HTTP_REFERER'], "//www.google.") || strpos($_SERVER['HTTP_REFERER'], "//google.")) {
    echo "Google Referer";
} else {
    echo "No Referer";
} 


will be rock solid.

Then again, my example isn't rock solid either after all, because you could have the above strings in a query string or even in the path, in theory, and it would give a false positive. You'll need to go all the way to http:// or https:// and make sure this is the very first thing in the string:

PHP Code:

if (strpos($_SERVER['HTTP_REFERER'], "http://www.google.") === 0 || strpos($_SERVER['HTTP_REFERER'], "http://google.") === 0 ||  strpos($_SERVER['HTTP_REFERER'], "https://www.google.") === 0 || strpos($_SERVER['HTTP_REFERER'], "https://google.") === 0) {
    echo "Google Referer";
} else {
    echo "No Referer";
} 


It would be more efficient to use a switch construct as there is more than one "Google" and more than one search engine.