How to run a php script, only if X page redirects you to it

Question

If (If X Page redirect me here) 
{
run this code
}
else 
{
run this code
}

What to write in IF condition? What is the PHP Code?

Answer 1

Try $_SERVER variable

<?php
echo '<pre>';
print_r($_SERVER);
?>

Output (on phpfiddle.org)

Array
(
    [DOCUMENT_ROOT] => /home/xfiddlec/public_html/main
    [EE_HOST] => main.xfiddle.com
    [EE_LIB] => /home/xfiddlec/public_html/main/inclibs/
    [EE_LIB_PREFIX] => /home/xfiddlec/public_html/main/inclibs/
    [EE_ROOT] => /home/xfiddlec/public_html/main/
    [GATEWAY_INTERFACE] => CGI/1.1
    [HTTP_ACCEPT] => text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
    [HTTP_ACCEPT_LANGUAGE] => en-US,en;q=0.5
    [HTTP_CONNECTION] => close
    [HTTP_HOST] => main.xfiddle.com
    [HTTP_REFERER] => http://phpfiddle.org/
    [HTTP_UPGRADE_INSECURE_REQUESTS] => 1
    [HTTP_USER_AGENT] => Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0
    [HTTP_X_FORWARDED_FOR] => 157.49.9.71
    [HTTP_X_REAL_IP] => 157.49.9.71
    [PATH] => /bin:/usr/bin
    [PHPRC] => /home/xfiddlec/config
    [PROXY_ADDR] => 31.22.4.102
    [QUERY_STRING] => 
    [REDIRECT_STATUS] => 200
    [REMOTE_ADDR] => 157.49.9.71
    [REMOTE_PORT] => 56471
    [REQUEST_METHOD] => GET
    [REQUEST_URI] => /code_45646358.php
    [SCRIPT_FILENAME] => /home/xfiddlec/public_html/main/code_45646358.php
    [SCRIPT_NAME] => /code_45646358.php
    [SERVER_ADDR] => 31.22.4.102
    [SERVER_ADMIN] => webmaster@www.main.xfiddle.com
    [SERVER_NAME] => main.xfiddle.com
    [SERVER_PORT] => 80
    [SERVER_PROTOCOL] => HTTP/1.0
    [SERVER_SIGNATURE] => 
Apache Server at main.xfiddle.com Port 80


    [SERVER_SOFTWARE] => Apache
    [SITE_WEBMASTER] => PhpFiddle Webmaster
    [SITE_WEBMASTER_URI] => mailto:webmaster@xfiddle.com
    [TZ] => America/New_York
    [UNIQUE_ID] => WRaD3x8WBGYADWv4OMgAAAAN
    [PHP_SELF] => /code_45646358.php
    [REQUEST_TIME_FLOAT] => 1494647775.2
    [REQUEST_TIME] => 1494647775
    [argv] => Array
        (
        )

    [argc] => 0
)

You can use following value in if condition

if ( $_SERVER[HTTP_REFERER] == "some thing" ) {

    // do my job
} else {
    // do another job

}

Or You can pass some GET/POST parameters and check their existence in php page.

Answer 2

In your X page

If you navigating using anchor html

<a href="y.php?from_page=x" >y page</a>

(or) If your redirecting using php header()

header('Location:y.php?from_page=x');

In Y page

php

if(isset($_GET['from_page']) && $_GET['from_page']=='x')
{ 
  echo "run this code "; 
}
else 
{ 
   echo " run this coe ";
} 

Answer 3

you can use $_SERVER['HTTP_REFERER'] to get the request referer. Refer to this post for get referer.

if ($_SERVER['HTTP_REFERER'] = "X page path") 
{
  //run this code
}
else 
{
  //run this code
}