检测正在访问该应用的网址

I am currently developing a PHP application that is (hopefully) going into production use soon.

What I'm needing help with is detecting what URL the app is being accessed on ie dev.local, testing.domain.com or app.domain.com and then using the correct MySQL DB, ie app_test for dev and testing and app_prod for the production server.

Along with that, I also want to be able to modify the internal URL's to match (several emails are sent that also need to be tested with the correct URL).

I remember seeing some stuff about it before but am not able to find it anymore, so hoping someone here can point me in the right direction.

Get full url of page

function request_url() {
  $result = ''; 
  $default_port = 80; 

  if (isset($_SERVER['HTTPS']) && ($_SERVER['HTTPS']=='on')) {
    $result .= 'https://';
    $default_port = 443;
  } else {
    $result .= 'http://';
  }

  $result .= $_SERVER['SERVER_NAME'];

  if ($_SERVER['SERVER_PORT'] != $default_port) {
    $result .= ':'.$_SERVER['SERVER_PORT'];
  }

  $result .= $_SERVER['REQUEST_URI'];
  return $result;
}

I think you will be enough: $_SERVER['SERVER_NAME']

Easy way to do that ......

Define environment constants in constants.php file

// constants.php

define('ENVIRONMENT', 'development');
//define('ENVIRONMENT', 'production');  // uncomment this when your going to live your project

define general functions in general.php

// general.php
include "constants.php";
function is_production()
{
    if(ENVIRONMENT == "production")
    {
        return TRUE;
    }
    return FALSE;
}

function is_development()
{
    if(ENVIRONMENT == "development")
    {
        return TRUE;
    }
    return FALSE;
}

Now you can us that functions in your database connection files and select your database and base url

// in db.php
include "general.php";

if(is_production())
{
     $conn = mysql_connect("host1","username1","password1");
     mysql_select_db("db1",$conn);
     define('BASE_URL', 'http://domain.com');
}
else if(is_development())
{
     $conn = mysql_connect("host2","username2","password2");
     mysql_select_db("db1",$conn);
     define('BASE_URL', 'http://testing.domain.com');
}

Now You can use that BASE_URL constant and you have database connection as you want This general overview but you can implement in your project as your standered.. :)